Terminal apparatus, base station apparatus, and communication method

ABSTRACT

To provide a terminal apparatus, a base station apparatus, and a communication method that enable a communication apparatus (terminal apparatus and/or base station apparatus) supporting multiple subcarrier spacings to perform efficient communication. A terminal apparatus includes: a control unit configured to identify a subcarrier spacing set applicable to a data channel, based on a first parameter included in higher layer signaling; and a reception unit configured to receive a control channel including data channel assignment information. Based on a type of the data channel assignment information, the terminal apparatus selects, from the subcarrier spacing set, a subcarrier spacing applicable to the data channel assigned based on the data channel assignment information.

TECHNICAL FIELD

Embodiments of the present invention relate to a technique of a terminalapparatus, a base station apparatus, and a communication method thatenable efficient communication.

BACKGROUND ART

The 3rd Generation Partnership Project (3GPP), which is astandardization project, standardized the Evolved Universal TerrestrialRadio Access (hereinafter, referred to as E-UTRA), in which high-speedcommunication is realized by adopting an Orthogonal Frequency-DivisionMultiplexing (OFDM) communication scheme and flexible scheduling using aunit of prescribed frequency and time called resource block.

Moreover, the 3GPP discusses Advanced E-UTRA, which realizeshigher-speed data transmission and has upper compatibility with E-UTRA.E-UTRA relates to a communication system based on a network in whichbase station apparatuses have substantially the same cell configuration(cell size); however, regarding Advanced E-UTRA, discussion is made on acommunication system based on a network (different-type radio network,Heterogeneous Network) in which base station apparatuses (cells) havingdifferent configurations coexist in the same area. In this regard,E-UTRA is also referred to as “Long Term Evolution (LTE)”, and AdvancedE-UTRA is also referred to as “LTE-Advanced”. Furthermore, LTE may be acollective name including LTE-Advanced.

Further, in the 3GPP, proposal has been made for the fifth generationcommunication (NPL 1). The fifth generation radio communicationtechnology/fifth generation radio access technology are sometimesreferred to as NX or Next Generation Radio Access Technology (NGRAT).

CITATION LIST Non Patent Literature

-   NPL 1: RWS-150009, Ericsson, 3GPP RAN Workshop on 5G, 17-18 Sep.    2015.

SUMMARY OF INVENTION Technical Problem

The present invention provides a terminal apparatus, a base stationapparatus, and a communication method that enable a communicationapparatus (terminal apparatus and/or base station apparatus) supportingmultiple subcarrier spacings to perform efficient communication.

Solution to Problem

A terminal apparatus according to an aspect of the present inventionincludes: a control unit configured to identify a subcarrier spacing setapplicable to a data channel, based on a first parameter included inhigher layer signaling; and a reception unit configured to receive acontrol channel including data channel assignment information. Based onthe type of the data channel assignment information, the terminalapparatus selects, from the subcarrier spacing set, a subcarrier spacingapplicable to the data channel assigned based on the data channelassignment information.

A base station apparatus according to an aspect of the present inventionincludes: a transmission unit configured to transmit higher layersignaling including a first parameter associated with indicating asubcarrier spacing set applicable to a data channel; a transmission unitconfigured to transmit a control channel including data channelassignment information; and a transmission unit configured to transmit adata channel by using an applicable subcarrier spacing based on the typeof the data channel assignment information. The applicable subcarrierspacing is included in the subcarrier spacing set.

A communication method for a terminal apparatus according to an aspectof the present invention includes the steps of: identifying a subcarrierspacing set applicable to a data channel, based on a first parameterincluded in higher layer signaling; receiving a control channelincluding data channel assignment information; and selecting, based onthe type of the data channel assignment information, a subcarrierspacing applicable to the data channel associated with the data channelassignment information, from the subcarrier spacing set.

A communication method for a base station apparatus according to anaspect of the present invention includes the steps of: transmittinghigher layer signaling including a first parameter associated withindicating a subcarrier spacing set applicable to a data channel;transmitting a control channel including data channel assignmentinformation; and transmitting a data channel by using an applicablesubcarrier spacing based on the type of the data channel assignmentinformation. The applicable subcarrier spacing is included in thesubcarrier spacing set.

Advantageous Effects of Invention

According to the present embodiment, a communication apparatus (terminalapparatus and/or base station apparatus) supporting multiple subcarrierspacings can efficiently communicate.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a conceptual diagram illustrating an example of a radiocommunication system according to a present embodiment.

FIG. 2 is a diagram illustrating an example of a serving cell accordingto the present embodiment.

FIG. 3 is a diagram illustrating an example of carrier aggregationaccording to the present embodiment.

FIG. 4 is a diagram illustrating an example of a configuration of a slotaccording to the present embodiment.

FIG. 5 is a diagram illustrating an example of the configuration of theslot according to the present embodiment.

FIG. 6 is a diagram illustrating an example of resource blocks accordingto the present embodiment.

FIG. 7 is a diagram illustrating an example of resource blocks accordingto the present embodiment.

FIG. 8 is a diagram illustrating examples of a region in which controlinformation is transmitted and a region in which data and/or signalother than the control information is transmitted, according to thepresent embodiment.

FIG. 9 is a diagram illustrating an example of a radio resource usemethod according to the present embodiment.

FIG. 10 is a diagram illustrating an example of addition of CP accordingto the present embodiment.

FIG. 11 is a diagram illustrating an example of CSI measurement and/orRRM measurement according to the present embodiment.

FIG. 12 is a diagram illustrating an example of CSI measurement and/orRRM measurement according to the present embodiment.

FIG. 13 is a diagram illustrating an example of scheduling according tothe present embodiment.

FIG. 14 is a diagram illustrating an example of the scheduling accordingto the present embodiment.

FIG. 15 is a diagram illustrating an example of a synchronization signaltransmission method according to the present embodiment.

FIG. 16 is a diagram illustrating an example of a multicast datatransmission method according to the present embodiment.

FIG. 17 is a diagram illustrating an example of a table managingsubcarrier spacings according to the present embodiment.

FIG. 18 is a diagram illustrating an example of the table managingsubcarrier spacings according to the present embodiment.

FIG. 19 is a diagram illustrating an example of the table managingsubcarrier spacings according to the present embodiment.

FIG. 20 is a diagram illustrating an example of the table managingsubcarrier spacings according to the present embodiment.

FIG. 21 is a diagram illustrating an example of the table managingsubcarrier spacings according to the present embodiment.

FIG. 22 is a diagram illustrating an example of a block configuration ofa base station apparatus according to the present embodiment.

FIG. 23 is a diagram illustrating an example of a block configuration ofa terminal apparatus according to the present embodiment.

FIG. 24 is a diagram illustrating an example of the table managingsubcarrier spacings according to the present embodiment.

FIG. 25 is a diagram illustrating an example of the table managingsubcarrier spacings according to the present embodiment.

DESCRIPTION OF EMBODIMENTS First Embodiment

A first embodiment of the present invention will be described below. Adescription will be given by using a communication system (cellularsystem) in which a base station apparatus (base station, NodeB, oreNodeB (eNB)) and a terminal apparatus (terminal, mobile station, userdevice, or User equipment (UE)) communicate in a cell.

In the present embodiment, “X/Y” includes the meaning of “X or Y”. Inthe present embodiment, “X/Y” includes the meaning of “X and Y”. In thepresent embodiment, “X/Y” includes the meaning of “X and/or Y”.

In the description of the present embodiment, a description of downlinkcovers downlink in a normal cell and downlink in a LAA cell. Forexample, a description of a downlink subframe includes a downlinksubframe in a normal cell, a full subframe in a LAA cell, and a partialsubframe in a LAA cell.

A physical channel and a physical signal substantially used in EUTRA andAdvanced EUTRA will be described. The “channel” refers to a medium usedto transmit a signal, and the “physical channel” refers to a physicalmedium used to transmit a signal. In the present embodiment, thephysical channel may be used synonymously with “signal”. In the futureEUTRA and Advanced EUTRA, the physical channel may be added or itsconstitution and format type may be changed or added; however, thedescription of the present embodiment will not be affected even if suchchange or addition is made.

FIG. 1 is a conceptual diagram of a radio communication system accordingto the present embodiment. In FIG. 1, the radio communication systemincludes terminal apparatuses 1A to 1C and a base station apparatus 3.For explanation, the terminal apparatuses 1A to 1C are simply referredto as a terminal apparatus in the present embodiment. For explanation,the base station apparatus 3 is simply referred to as a base stationapparatus in the present embodiment.

The present embodiment may be applied to an RRC_CONNECTED state or onlyto the terminal apparatus in an RRC_CONNECTED mode. The presentembodiment may be applied to an RRC_IDLE state or only to the terminalapparatus in the RRC_IDLE state. The present embodiment may be appliedto both the RRC_CONNECTED state or the terminal apparatus in theRRC_CONNECTED mode and the RRC_IDLE state or the terminal apparatus inthe RRC_IDLE state.

In the present embodiment, one serving cell is configured for theterminal apparatus. The one serving cell may be a primary cell. The oneserving cell may be a cell on which the terminal apparatus is camping.The primary cell is a cell in which an initial connection establishmentprocedure has been performed, a cell in which a connectionre-establishment procedure has started, or a cell indicated as a primarycell in a handover procedure.

A carrier corresponding to a serving cell in the downlink is referred toas a downlink component carrier. A carrier corresponding to a servingcell in the uplink is referred to as an uplink component carrier. Thedownlink component carrier and the uplink component carrier arecollectively referred to as a component carrier. In FDD, the uplinkcomponent carrier and the downlink component carrier correspond todifferent carrier frequencies. In TDD, the uplink component carrier andthe downlink component carrier correspond to the same carrier frequency.

In the downlink, one independent HARQ entity exists for each servingcell (downlink component carrier). The HARQ entity manages multiple HARQprocesses in parallel. Each of the HARQ processes indicates a physicallayer to receive data, based on a received downlink assignment (downlinkcontrol information).

In the downlink, at least one transport block is generated for each ofone or multiple Transmission Time Intervals (TTIs) for each servingcell. The transport block and HARQ retransmission of the transport blockare mapped to one serving cell. Note that, in LTE, a TTI serves as asubframe. The transport block in the downlink is MAC layer datatransmitted on the Downlink Shared CHannel (DL-SCH).

In the present embodiment, in the downlink, “transport block”, “MACProtocol Data Unit (PDU)”, “MAC layer data”, “DL-SCH”, “DL-SCH data”,and “downlink data” are assumed to mean the same.

FIG. 2 is an example of a serving cell according to the presentembodiment. The serving cell in FIG. 2 may be rephrased as a downlinkserving cell, downlink component carrier, or the like. One serving cellmay include multiple regions. FIG. 2 illustrates an example in whichthree regions are included in one serving cell. Although notillustrated, a guard frequency may be present between the regions.Although not illustrated, the regions may overlap each other. In otherwords, no guard frequency may be present between the regions. The numberof regions included in one serving cell may be limited. For example, thenumber of regions included in one serving cell may be limited to up tofive. The regions included in one serving cell may include a region usedfor downlink transmission and a region used for uplink transmission. Forexample, a first region and a second region may be used for downlinktransmission, and a third region may be used for uplink transmission.

Different subcarrier spacings may be applied to the respective regionsincluded in one serving cell. For example, a first subcarrier spacingmay be applied to the first region, a second subcarrier spacing may beapplied to the second region, and a third subcarrier spacing may beapplied to the third region. The subcarrier spacings applied to theregions may be determined based on some of or all Element (1) to Element(4) to be described later.

Moreover, the terminal apparatus and the base station apparatus mayemploy a technique for aggregating the frequencies (serving cells,cells, component carriers, or frequency bands) of multiple differentfrequency bands through carrier aggregation and treating the resultantas a single frequency (frequency band). Component carriers arecategorized into an uplink component carrier corresponding to the uplinkand a downlink component carrier corresponding to the downlink. Thecarrier aggregation may be referred to as cell aggregation.

For example, in a case that each of five component carriers having afrequency bandwidth of 20 MHz are aggregated through carrieraggregation, a terminal apparatus capable of performing carrieraggregation performs transmission and/or reception by assuming that theaggregated carrier has a frequency bandwidth of 100 MHz. Note thatcomponent carriers to be aggregated may have contiguous frequencies orfrequencies some or all of which are discontiguous. For example,assuming that available frequency bands are an 800 MHz band, a 2 GHzband, and a 3.5 GHz band, a component carrier may be transmitted in the800 MHz band, another component carrier may be transmitted in the 2 GHzband, and yet another component carrier may be transmitted in the 3.5GHz band.

It is also possible to aggregate multiple contiguous or discontiguouscomponent carriers of the same frequency band. The frequency bandwidthof each component carrier may be narrower (e.g., 5 MHz or 10 MHz) thanthe receivable frequency bandwidth (e.g., 20 MHz) of the terminalapparatus, and the frequency bandwidth of component carriers to beaggregated may be different from each other. Each frequency bandwidth ispreferably equal to any of the frequency bandwidth of known cells inconsideration of backward compatibility, but may be a frequencybandwidth different from any of the frequency bands of the known cells.

FIG. 3 is an example of carrier aggregation according to the presentembodiment. FIG. 3 is an example in which a serving cell 1 and a servingcell 2 are aggregated. The serving cell 1 includes the first region tothe third region, and the serving cell 2 includes a fourth region and afifth region.

It is preferable that any one of serving cells among the multipleserving cells thus aggregated be a primary cell, and the serving cellsother than the primary cell among the multiple serving cell thusaggregated may be secondary cells. For example, the serving cell 1 maybe a primary cell, and the serving cell 2 may be a secondary cell. Oneregion in the primary cell may be a primary region. The primary regionmay also be present in the secondary cell. For example, the first regionin the serving cell 1, which is the primary cell, may be a primaryregion, and the fourth region in the serving cell 2, which is thesecondary cell, may be a primary secondary region.

FIG. 4 and FIG. 5 are diagrams illustrating configurations of a slotaccording to the present embodiment. In the present embodiment, a normalCyclic Prefix (CP) may be applied to symbols. The physical signal or thephysical channel transmitted in each of the slots is expressed by aresource grid. In FIG. 4 and FIG. 5, the horizontal axis represents atime axis, and the vertical axis represents a frequency axis. In thedownlink, the resource grid is defined by multiple subcarriers andmultiple symbols. In the uplink, the resource grid is defined bymultiple subcarriers and multiple symbols. The symbols in the downlinkmay be OFDM symbols, filtered OFDM symbols, or DFT-S-OFDM symbols. Thesymbols in the uplink may be OFDM symbols, filtered OFDM symbols,SC-FDMA symbols, or DFT-S-OFDM symbols. The number of subcarriersconstituting one slot depends on a cell bandwidth. Each element withinthe resource grid is referred to as a resource element. The resourceelement is identified by using a subcarrier number and a symbol number.It is apparent that the symbol length increases in a case of configuringa smaller subcarrier spacing and that the symbol length decreases in acase of configuring a larger subcarrier spacing. Configuring a smallersubcarrier spacing is the same as configuring a narrower subcarrierbandwidth, and configuring a larger subcarrier spacing is the same asconfiguring a wider subcarrier bandwidth.

A difference between FIG. 4 and FIG. 5 will be described. In FIG. 4, thesubcarrier bandwidth (subcarrier spacing) is variable in the frequencydomain but is not variable in the time domain. In other words, multiplesubcarrier spacings coexist for a certain symbol in FIG. 4. In FIG. 5,the subcarrier bandwidths (subcarrier spacings) are not variable in thefrequency domain but are variable in the time domain. In other words,multiple subcarrier spacings do not coexist for a certain symbol in FIG.5. Although not illustrated, the subcarrier spacing may besemi-statistically variable or dynamically variable in the time domainin FIG. 4. Although not illustrated, the subcarrier spacing may besemi-statistically variable in the time domain in FIG. 4. In otherwords, the subcarrier spacing may not necessarily be dynamicallyvariable in the time domain in FIG. 4. Although not illustrated, thesubcarrier spacing may be semi-statistically variable or dynamicallyvariable in the frequency domain in FIG. 5. Although not illustrated,the subcarrier spacing may be semi-statistically variable in thefrequency domain in FIG. 5. In other words, the subcarrier spacing maynot necessarily be dynamically variable in the frequency domain in FIG.5.

FIG. 6 is an example of resource blocks according to the presentembodiment. Each region defined (specified) by a prescribed number ofsubcarriers and a prescribed number of symbols may be defined as aresource block. FIG. 6 is a diagram of a case that each region defined(specified) by four subcarriers in the frequency domain and four symbolsin the time domain is defined as a resource block. As illustrated inFIG. 6, in a case that multiple subcarrier spacings are applicable, thefrequency bandwidth and the time length defining (specifying) eachresource block vary based on the applied subcarrier spacing. Forexample, a resource block is defined (specified) by a bandwidth of Y/2kHz and a time of 2*B ms, a resource block is defined (specified) by abandwidth of Y kHz and a time of B ms, and a resource block is defined(specified) by a bandwidth of 2*Y kHz and a time of B/2 ms. Although notillustrated, multiple subcarrier spacings and/or symbol lengths may beincluded in one resource block.

Although a description has been given of an example in which eachresource block is defined as a region defined (specified) by theprescribed number of subcarriers and the prescribed number of symbols,each resource block may be defined only by a prescribed number ofsubcarriers or a prescribed number of symbols. In other words, eachresource block may be defined using only the time domain or thefrequency domain. In other words, each region defined (specified) by aprescribed number of subcarriers and/or a prescribed number of symbolsmay be defined as a resource block.

FIG. 7 is an example of resource blocks according to the presentembodiment. Each region defined (specified) by a prescribed frequencybandwidth and a prescribed time (symbol time) may be defined as aresource block. FIG. 7 is a diagram of a case that each region defined(specified) by a bandwidth Y kHz and a time B ms is defined as aresource block. As illustrated in FIG. 7, in a case that multiplesubcarrier spacings are applicable, the number of subcarriers and thenumber of symbols defining (specifying) one resource block varies. Forexample, a resource block is defined (specified) by eight subcarriersand two symbols, a resource block is defined (specified) by foursubcarriers and four symbols, and a resource block is defined(specified) by two subcarriers and eight symbols. Although notillustrated, multiple subcarrier spacings and/or symbol lengths may beincluded in one resource block.

Although a description has been given of an example in which each regiondefined (specified) by the prescribed frequency bandwidth and theprescribed time is defined as a resource block, each resource block maybe defined only by a prescribed frequency bandwidth or a prescribedtime. In other words, each resource block may be defined using only thetime domain or the frequency domain. In other words, each region defined(specified) by a prescribed frequency bandwidth and/or a prescribed timemay be defined as a resource block.

A resource block may be used to express mapping of a certain physicalchannel (such as a downlink data channel (e.g., PDSCH) or an uplink datachannel (e.g., PUSCH)) to resource elements. For the resource block, avirtual resource block and a physical resource block may be defined. Acertain physical channel may first be mapped to the virtual resourceblock. Thereafter, the virtual resource block may be mapped to thephysical resource block. The physical resource blocks may be numberedfrom zero in the frequency domain. The resource block may be referred toas a chunk.

FIG. 8 is an example illustrating a region in which control informationis transmitted and a region in which data and/or signal other than thecontrol information is transmitted, according to the present embodiment.The region in which control information is transmitted may be referredto as a control channel, and the control channel may be a downlinkcontrol channel (e.g., PDCCH). The region in which data and/or signalother than control information is transmitted may include at least aregion in which user data (channel, e.g., PDSCH, for example) istransmitted. The region in which control information is transmitted maybe a prescribed subcarrier spacing. The region in which controlinformation is transmitted and the region controlled by the controlinformation transmitted in the region in which the control informationis transmitted may have the same subcarrier spacing. The region in whichcontrol information is transmitted and the region controlled by thecontrol information transmitted in the region in which the controlinformation is transmitted may have different subcarrier spacings.

FIG. 9 is an example of a radio resource use method according to thepresent embodiment.

A radio resource use method illustrated in (1) of FIG. 9 will bedescribed. In (1), a region in which control information is transmittedis at the beginning in the time domain, and subsequently referencesignals (RSs) are transmitted in a distributed manner in the frequencydomain and the time domain. The region in which neither the controlsignals nor the reference signals is transmitted may be used for datatransmission. Although not illustrated, reference signals (RSs) may alsobe transmitted in the region for transmitting control information. Areference signal transmitted in the region for transmitting controlinformation (reference signal for control information) and a referencesignal transmitted in the region for transmitting data (reference signalfor data) may be different from each other.

A radio resource use method illustrated in (2) of FIG. 9 will bedescribed. In (2), a region for transmitting reference signals(reference burst) is at the beginning in the time domain and is followedby a region for transmitting control information (control burst) and aregion for transmitting data (data burst). The region in which neitherthe control signal nor the reference signals is transmitted may be usedfor data transmission. The reference signals transmitted in thereference burst may be associated with signals transmitted in thecontrol burst and/or data burst. Specifically, the reference signalstransmitted in the reference burst may be used for demodulation of thesignals transmitted in the control burst and/or data burst. Thereference signals for the control information burst and the referencesignals for the data burst may be different. Different subcarrierspacings may be applied to the respective bursts (reference burst,control burst, and data burst). For example, the subcarrier spacing tobe applied to each of the bursts may be notified at the beginning (firstsymbol or first multiple symbols) of the burst. For example,notification may be made in each burst, regarding the subcarrier spacingto be applied to the next burst continuous to the burst in terms oftime. For example, the subcarrier spacing of the burst (data burst)controlled by the control information transmitted by a control burst maybe notified in the control burst. A gap may be present between thebursts, although not illustrated.

A radio resource use method illustrated in (3) of FIG. 9 will bedescribed. In (3), a region for downlink transmission (downlink burst)is at the beginning in the time domain and is followed by a region foruplink transmission (uplink burst). In the downlink burst, some of orall control signals, data signals, and reference signals may betransmitted. In the uplink burst, some of or all a control signal, adata signal, and a reference signal may be transmitted. Differentsubcarrier spacings may be applied to the respective bursts (downlinkburst and uplink burst). For example, the subcarrier spacing to beapplied to each of the bursts may be notified at the beginning (firstsymbol or first multiple symbols) of the burst. A gap may be presentbetween the bursts, although not illustrated. For example, notificationmay be made in a downlink burst, regarding the subcarrier spacing to beapplied to the uplink burst contiguous to the downlink burst in terms oftime.

FIG. 10 is an example of addition of CP according to the presentembodiment. It is apparent that the symbol length increases in a case ofconfiguring a smaller subcarrier spacing and that the symbol lengthdecreases in a case of configuring a larger subcarrier spacing.Configuring a smaller subcarrier is the same as configuring a narrowersubcarrier bandwidth, and configuring a larger subcarrier spacing is thesame as configuring a wider subcarrier bandwidth. In other words, FIG.10 illustrates that CPs having different lengths are added to symbolshaving different symbol lengths. In other words, the symbol length andthe length of the CP may correspond to each other. Specifically, a firstCP is added to a symbol having a first symbol length, a second CP isadded to a symbol having a second symbol length, . . . , and an x-th CPis added to an x-th symbol length. The CP (CP length) to be added may bedetermined based on the symbol length of the symbol to which the CP isadded, that is, the CP (CP length) to be added may be implicitlydetermined based on the symbol length of the symbol to which the CP isto be added. The CP (CP length) to be added may be explicitly notifiedby the base station apparatus (may be notified (transmitted) by using L1or higher layer signaling). Having different symbol lengths is the sameas having different subcarrier spacings. In other words, a symbol lengthcan be rephrased as a subcarrier spacing.

FIG. 11 is an example of CSI measurement and/or RRM measurementaccording to the present embodiment. The Channel State Information (CSI)may be measured based on a reference signal. For example, the CSI may bemeasured based on a channel state information reference signal (CSI-RS)or a Cell-specific RS (CRS). The CSI includes a Channel QualityIndicator (CQI), a Precoding Matrix Indicator (PMI), a Precoding TypeIndicator (PTI), and a Rank Indication (RI), which may be usedrespectively for specifying (representing) a preferable modulationscheme and coding rate, a preferable precoding matrix, a preferable PMItype, and a preferable rank. Note that each of the Indicators may bedenoted as Indication. Moreover, the CQI and the PMI may be classifiedinto wideband CQI and PMI assuming channel transmission using all theresource blocks in a single cell, and subband CQI and PMI assumingchannel transmission using some contiguous resource blocks (subbands) ina single cell. Moreover, PMI may include a type of PMI, which representsa single preferable precoding matrix using two types of PMIs, which area first PMI and a second PMI, in addition to a normal type of PMI, whichrepresents a single preferable precoding matrix using a single PMI.Radio Resource Management measurement (RRM measurement) may bemeasurement associated with RSRP measurement, RSRQ measurement, and RSSImeasurement. The RRM measurement may be performed based on a referencesignal, such as a CRS or a CSI-RS.

Even in a case, as in FIG. 11, that a base station apparatus usesmultiple different subcarrier spacings, a terminal apparatus may performCSI measurement and/or RRM measurement by assuming the downlinkbandwidth of channel transmission with a prescribed subcarrier spacing.Note that “perform CSI measurement and/or RRM measurement by assumingthe downlink bandwidth with a prescribed subcarrier spacing” meansperforming CSI measurement and/or RRM measurement by assuming that theprescribed subcarrier spacing is applied to the entire downlinkbandwidth. Here, the prescribed subcarrier spacing may be defined inadvance, may be explicitly notified by the base station apparatus (maybe notified (transmitted) by using L1 or higher layer signaling), or maybe determined by the terminal apparatus (implicitly determined).

FIG. 12 is an example of CSI measurement and/or RRM measurementaccording to the present embodiment. In a case that a base stationapparatus uses multiple different subcarrier spacings, the terminalapparatus may perform CSI measurement and/or RRM measurement by using afrequency band to which a prescribed subcarrier spacing is applied. Forexample, in a case as in FIG. 12, that first subcarrier spacing(subcarrier bandwidth) and a second subcarrier spacing are used fordownlink transmission, the terminal apparatus may perform CSImeasurement and/or RRM measurement by using a frequency band to whichthe first subcarrier spacing is applied. The subcarrier spacing and/orthe frequency position to be used for CSI measurement and/or RRMmeasurement may be defined in advance, may be explicitly notified by thebase station apparatus (may be notified (transmitted) by using L1 orhigher layer signaling), or may be determined by the terminal apparatus(implicitly determined). The subcarrier spacing and/or the frequencyposition not to be used for CSI measurement and/or RRM measurement maybe defined in advance, may be explicitly notified by the base stationapparatus (may be notified (transmitted) by using L1 or higher layersignaling), or may be determined by the terminal apparatus (implicitlydetermined). The subcarrier spacing to be used for CSI measurementand/or RRM measurement may be determined based on some of or all Element(1) to Element (4) to be described later. The subcarrier spacing for ameasurement object relating to the RRM measurement may be determinedbased on some of or all Element (1) to Element (4) to be describedlater. The measurement object relating to the RRM measurement mayinclude information associated with the subcarrier spacing. Themeasurement object relating to the RRM measurement may includeinformation associated with a CP (CP length). The measurement objectrelating to the RRM measurement may include information associated witha frequency position (such as information indicating a band, informationindicating an operating band, or information indicating a carrierfrequency). The measurement object relating to the RRM measurement mayinclude information associated with cell identification (such as a cellID or the ID of a measurement target cell).

FIG. 13 is an example of scheduling (self scheduling) according to thepresent embodiment. “Self scheduling” in the present embodiment meansthat, for example, in FIG. 2, the region for transmitting controlinformation is present in the x-th region (x is any number) and theregion controlled by the control information is present in the x-thregion. In other words, in FIG. 2, the region for transmitting controlinformation and the region controlled by the control information arepresent in the same x-th region.

Scheduling illustrated in (1) of FIG. 13 (self scheduling) will bedescribed. (1) is an example that the region in which controlinformation is transmitted and a region in which data and/or signalother than the control information is transmitted have the samesubcarrier spacing. In other words, the region in which controlinformation is transmitted (e.g., a region 1 in FIG. 13) and the regioncontrolled by the control information (e.g., a region 2 in FIG. 13) havethe same subcarrier spacing. In (1), the region in which controlinformation is transmitted and the region controlled by the controlinformation may be prohibited from having different subcarrier spacings.

Scheduling illustrated in (2) of FIG. 13 (self scheduling) will bedescribed. (2) is an example that the region in which controlinformation is transmitted and a region in which data and/or signalother than the control information is transmitted have differentsubcarrier spacings. In other words, the region in which controlinformation is transmitted (e.g., a region 3 in FIG. 13) and the regioncontrolled by the control information (e.g., a region 4 in FIG. 13) havedifferent subcarrier spacings.

FIG. 14 is an example of scheduling (cross scheduling) according to thepresent embodiment. “Cross scheduling” in the present embodiment meansthat, for example, in FIG. 2, the region in which control information istransmitted is present in the x-th region (x is any number) and theregion controlled by the control information is present in the x-thregion (y is any number different from x). In other words, in FIG. 2,the region in which control information is transmitted and the regioncontrolled by the control information are present in different regions.

Scheduling illustrated in (1) of FIG. 14 (cross scheduling) will bedescribed. (1) is an example that the region in which controlinformation is transmitted and a region in which data and/or signalother than the control information is transmitted have differentsubcarrier spacings. In other words, the region in which controlinformation is transmitted (e.g., a region 1 in FIG. 14) and the regioncontrolled by the control information (e.g., a region 2 in FIG. 14) mayhave different subcarrier spacings.

Scheduling illustrated in (2) of FIG. 14 (cross scheduling) will bedescribed. (2) is an example that the region in which controlinformation is transmitted and a region in which data and/or signalother than the control information is transmitted have the samesubcarrier spacing. In other words, the region in which controlinformation is transmitted (e.g., a region 3 in FIG. 14) and the regioncontrolled by the control information (e.g., a region 4 in FIG. 14) havethe same subcarrier spacing. In (2), the region in which controlinformation is transmitted and the region controlled by the controlinformation may be prohibited from having different subcarrier spacings.For example, the region 3 in FIG. 14 may be prohibited from controllinga region 5 in FIG. 14.

FIG. 15 is an example of a Synchronization signal transmission methodaccording to the present embodiment. The Synchronization signal (SS) isused for a terminal apparatus to be synchronized in terms of frequencyand time domains in the downlink. In the TDD scheme, the Synchronizationsignal may be mapped to subframes 0, 1, 5, and 6 within a radio frame.In the FDD scheme, the Synchronization signal may be mapped to subframes0 and 5 within a radio frame. The Synchronization signal may include aPrimary synchronization signal (PSS) and the Secondary synchronizationsignal (PSS). Even in a case that the Synchronization signal istransmitted in the frequency band to which multiple subcarrier spacingsare applicable, a prescribed subcarrier spacing may always be applied totransmission of the Synchronization signal. The prescribed subcarrierspacing applied to the transmission of the Synchronization signal may bedetermined based on some of or all Element (1) to Element (4) to bedescribed later.

FIG. 16 is an example of a multicast data transmission method accordingto the present embodiment. Multicast data transmission may betransmission associated with Multimedia Broadcast multicast serviceSingle Frequency Network (MBSFN). For example, multicast datatransmission may be transmission of MBSFN subframes. Terminalapparatuses may be divided into multiple MBSFN groups. Note thatdivision to the MBSFN groups may be based on services in which theterminal apparatuses are interested. Division to the MBSFN groups may bebased on requirements of the services in which the terminal apparatusesare interested. The subcarrier spacing to be applied may be differentfor each MBSFN group. For example, the first subcarrier spacing may beused for MBSFN group 1, the second subcarrier spacing may be used forMBSFN group 2, . . . , and the x-th subcarrier spacing may be used forMBSFN group x. Note that multiple MBSFN groups may befrequency-multiplexed, time-multiplexed, or code-multiplexed. Thesubcarrier spacings for the MBSFN groups may be determined based on someof or all Element (1) to Element (4) to be described later. Eachterminal apparatus may select an MBSFN group and a cell corresponding tothe MBSFN group, based on the subcarrier spacings for the MBSFN groups.

FIG. 22 is a schematic diagram illustrating an example of a blockconfiguration of a base station apparatus according to the presentembodiment. The base station apparatus includes a higher layer(higher-layer control information notification unit, higher layerprocessing unit) 2201, a control unit (base station control unit) 2202,a codeword generation unit 2203, a downlink subframe generation unit2204, an OFDM signal transmission unit (downlink transmission unit)2206, a transmit antenna (base station transmit antenna) 2207, a receiveantenna (base station receive antenna) 2208, an SC-FDMA signal receptionunit (CSI reception unit) 2209, and an uplink subframe processing unit2210. The downlink subframe generation unit 2204 includes a downlinkreference signal generation unit 2205. Moreover, the uplink subframeprocessing unit 2210 includes an uplink control information extractionunit (CSI acquisition unit) 2211. Note that the transmit antenna 2207may be referred to as a base station transmit antenna 2207, and thereceive antenna 2208 may be referred to as a base station receiveantenna 2208.

FIG. 23 is a schematic diagram illustrating an example of a blockconfiguration of a terminal apparatus according to the presentembodiment. The terminal apparatus includes a receive antenna (terminalreceive antenna) 2301, an OFDM signal reception unit (downlink receptionunit) 2302, a downlink subframe processing unit 2303, a transport blockextraction unit (data extraction unit) 2305, a control unit (terminalcontrol unit) 2306, a higher layer (higher-layer control informationacquisition unit, higher layer processing unit) 2307, a channel statemeasurement unit (CSI generation unit) 2308, an uplink subframegeneration unit 2309, SC-FDMA signal transmission units (UCItransmission units) 2311 and 2312, and transmit antennas (terminaltransmit antennas) 2313 and 2314. The downlink subframe processing unit2303 includes a downlink reference signal extraction unit 2304.Moreover, the uplink subframe generation unit 2309 includes an uplinkcontrol information generation unit (UCI generation unit) 2310. Thetransmit antenna 2313 may be referred to as a terminal transmit antenna2313, the transmit antenna 2314 may be referred to as a terminaltransmit antenna 2314, and the receive antenna 2301 may be referred toas a terminal receive antenna 2301.

First, a flow of downlink data transmission and/or reception will bedescribed with reference to FIG. 22 and FIG. 23. In the base stationapparatus, the control unit 2202 holds a Modulation and Coding Scheme(MCS) indicating a modulation scheme, a coding rate, and the like in thedownlink, a downlink resource allocation indicating RBs to be used fordata transmission, and information to be used for HARQ control (aredundancy version, an HARQ process number, and a new data indicator)and controls the codeword generation unit 2203 and the downlink subframegeneration unit 2204, based on these elements. Downlink data (alsoreferred to as a downlink transport block) transmitted from the higherlayer 2201 is processed through error correction coding, rate matching,and the like in the codeword generation unit 2203 under the control ofthe control unit 2202 and then, a codeword is generated. Two codewordsat maximum are transmitted at the same time in a single subframe of asingle cell. The control unit 2202 indicates the downlink subframegeneration unit 2204 to generate a downlink subframe. First, a codewordgenerated in the codeword generation unit 2203 is converted into amodulation symbol sequence through a modulation process, such as PhaseShift Keying (PSK) modulation or Quadrature Amplitude Modulation (QAM).Moreover, a modulation symbol sequence is mapped onto REs of some RBs,and a downlink subframe for each antenna port is generated through aprecoding process. In this operation, the transmission data sequencetransmitted from the higher layer 2201 includes higher-layer controlinformation, which is control information about the higher layer (e.g.,dedicated (individual) Radio Resource Control (RRC) signaling).Furthermore, the downlink reference signal generation unit 2205generates a downlink reference signal. The downlink subframe generationunit 2204 maps the downlink reference signal to the REs in the downlinksubframes in accordance with an indication from the control unit 2202.The OFDM signal transmission unit 2206 modulates the downlink subframegenerated by the downlink subframe generation unit 2204 to an OFDMsignal, and then transmits the OFDM signal through the transmit antenna2207. Although a configuration including one OFDM signal transmissionunit 2206 and one transmit antenna 2207 is provided as an example here,a configuration including multiple OFDM signal transmission units 2206and multiple transmit antennas 2207 may be employed in a case thatdownlink subframes are transmitted on multiple antenna ports.Furthermore, the downlink subframe generation unit 2204 may also have acapability of generating physical-layer downlink control channels, suchas a PDCCH and an EPDCCH, to map the channels to REs in the downlinksubframes. Multiple base station apparatuses (base station apparatus −1and base station apparatus −2) transmit separate downlink subframes. Thereceive antenna 2208 receives an SC-FDMA signal and a CSI and conveysthe received signals to the SC-FDMA signal reception unit 2209.Moreover, the SC-FDMA signal reception unit 2209 conveys data to theuplink subframe processing unit 2210. Moreover, the uplink subframeprocessing unit 2210 extracts uplink control information in the uplinkcontrol information extraction unit 2211.

In the terminal apparatus, an OFDM signal is received by the OFDM signalreception unit 2302 through the receive antenna 2301, and an OFDMdemodulation process is performed on the signal. The downlink subframeprocessing unit 2303 first detects physical-layer downlink controlchannels, such as a PDCCH and an EPDCCH. More specifically, the downlinksubframe processing unit 2303 decodes the signal by assuming that aPDCCH and an EPDCCH have been transmitted in the regions to which thePDCCH and the EPDCCH can be assigned, and checks Cyclic Redundancy Check(CRC) bits added in advance (blind decoding). In other words, thedownlink subframe processing unit 2303 monitors a PDCCH and an EPDCCH.In a case that the CRC bits match an ID (a single terminal-specificidentifier assigned to a single terminal, such as a Cell-Radio NetworkTemporary Identifier (C-RNTI) or a Semi Persistent Scheduling-C-RNTI(SPS-C-RNTI), or a Temporary C-RNTI) assigned by the base stationapparatus beforehand, the downlink subframe processing unit 2303recognizes that a PDCCH or an EPDCCH has been detected and extracts aPDSCH by using control information included in the detected PDCCH orEPDCCH. The control unit 2202 holds an MCS indicating a modulationscheme, a coding rate, and the like in the downlink based on the controlinformation, a downlink resource allocation indicating RBs to be usedfor downlink data transmission, and information to be used for HARQcontrol, and controls the downlink subframe processing unit 2303, thetransport block extraction unit 2305, and the like, in accordance withthese elements. More specifically, the control unit 2202 performscontrol so as to carry out an RE demapping process, a demodulationprocess, and the like corresponding to the RE mapping process and themodulation process in the downlink subframe generation unit 2204. ThePDSCH extracted from the received downlink subframe is transmitted tothe transport block extraction unit 2305. Furthermore, the downlinkreference signal extraction unit 2304 in the downlink subframeprocessing unit 2303 extracts the downlink reference signal from thedownlink subframe. In the transport block extraction unit 2305, a ratematching process, a rate matching process corresponding to errorcorrection coding, error correction decoding, and the like in thecodeword generation unit 2203 are performed, and a transport block isextracted and transmitted to the higher layer 607. The transport blockincludes higher-layer control information, and the higher layer 2201notifies the control unit 2202 of a necessary physical-layer parameter,based on the higher-layer control information. Multiple base stationapparatuses (base station apparatus −1 and base station apparatus −2)transmit separate downlink subframes, and the terminal apparatusreceives the downlink subframes. Hence, the above-described processesmay be performed for the downlink subframe of each of the multiple basestation apparatuses. In this situation, the terminal apparatus mayrecognize or may not necessarily recognize that multiple downlinksubframes have been transmitted from the multiple base stationapparatuses. In a case that the terminal apparatus does not recognize asabove, the terminal apparatus may simply recognize that multipledownlink subframes have been transmitted in multiple cells. Moreover,the transport block extraction unit 2305 determines whether thetransport block has been detected correctly, and transmits adetermination result to the control unit 2202.

Next, a flow of uplink signal transmission and/or reception will bedescribed. In the terminal apparatus, under the indication of thecontrol unit 2306, a downlink reference signal extracted by the downlinkreference signal extraction unit 2304 is transmitted to the channelstate measurement unit 2308, and, in the channel state measurement unit2308, the channel state and/or interference is measured, and further CSIis calculated based on the measured channel state and/or interference.The control unit 2306 indicates the uplink control informationgeneration unit 2310 to generate an HARQ-ACK (DTX (not transmitted yet),ACK (detection success), or NACK (detection failure)) and to map theHARQ-ACK to a downlink subframe, based on a determination result ofwhether the transport block is correctly detected. The terminalapparatus performs these processes on the downlink subframe of each ofmultiple cells. In the uplink control information generation unit 2310,a PUCCH including the calculated CSI and/or HARQ-ACK is generated. Inthe uplink subframe generation unit 2309, the PUSCH including the uplinkdata transmitted from the higher layer 2307 and the PUCCH generated bythe uplink control information generation unit 2310 are mapped to RBs inan uplink subframe, and an uplink subframe is generated. The uplinksubframe is subjected to the SC-FDMA modulation in the SC-FDMA signaltransmission unit 2311 to generate an SC-FDMA signal, and the SC-FDMAsignal transmission unit 2311 transmits the SC-FDMA signal via thetransmit antenna 2313.

For example, in the present embodiment, some of or all the followingsignals may be transmitted. Some of or all the following signals may betransmitted in the downlink. Some of or all the following signals may betransmitted in the uplink. Some of or all the following signals may betransmitted in both the downlink and the uplink.

-   -   Signal associated with synchronization    -   Signal associated with initial access    -   Signal associated with control    -   Signal associated with data    -   Reference signal

Some of or all the above signals may be transmitted from the basestation apparatus for one terminal apparatus and/or another base stationapparatus. Specifically, some of or all the above signals may betransmitted from the base station apparatus for one terminal apparatusand/or another base station apparatus at a certain time. “At a certaintime” can be rephrased as in a certain radio frame, in a certainsubframe, in a certain slot, in a certain symbol, or the like.

Some of or all the above signals may be transmitted from the basestation apparatus for multiple terminal apparatuses and/or multipleother base station apparatuses. Specifically, some of or all the abovesignals may be transmitted from the base station apparatus for multipleterminal apparatuses and/or other base station apparatuses at a certaintime. “At a certain time” can be rephrased as in a certain radio frame,in a certain subframe, in a certain slot, in a certain symbol, or thelike. “Transmitted for multiple terminal apparatuses and/or other basestation apparatuses” may mean that some of or all the above signals aretime-multiplexed (time division multiplexed), frequency-multiplexed(frequency division multiplexed), spatial multiplexed, orcode-multiplexed, for multiple terminal apparatuses and/or other basestation apparatuses. “At a certain time” can be rephrased as in acertain radio frame, in a certain subframe, in a certain slot, in acertain symbol, or the like.

Reference signals for some or all the above signals may be transmittedtogether with some or all the above signals. Reference signals may beassociated with some or all the above signals. Reference signals maycorrespond with some or all the above signals. Reference signals may bedifferent (independent) for some or all the above signals. For example,a first reference signal may be transmitted for a first signal, a secondreference signal may be transmitted for a second signal, . . . , and anx-th reference signal may be transmitted for an x-th signal. A referencesignal may be common to multiple signals. For example, the firstreference signal may be transmitted for the first signal, the firstreference signal may be transmitted for the second signal, and a thirdreference signal may be transmitted for a third signal. A referencesignal may be transmitted at the same time and/or frequency with that ofthe associated signal. For example, the reference signal may betransmitted in the same radio frame as that of the associated signal, inthe same subframe as that of the associated signal, in the same slot asthat of the associated signal, in the same symbol as that of theassociated signal, at the same carrier frequency as that of theassociated signal, at the same band as that of the associated signal, inthe same subcarrier as that of the associated signal, or the like. Thereference signal may be used for channel compensation of the associatedsignal. The reference signal may be used to calculate channelinformation (channel state information) of the associated signal. Thereference signal may be used to demodulate the associated signal. Thereference signals may be categorized into a downlink reference signal(reference signal transmitted in the downlink) and an uplink referencesignal (reference signal transmitted in the uplink). Each referencesignal may be transmitted in common for multiple terminal apparatuses ormay be transmitted individually for each terminal apparatus.

The Cyclic Prefix (CP, guard interval) may be applied to some of or allthe above signals. Not that “CP is applied” may mean that a CP istransmitted, a CP is added, a CP is applied to an associated signal, ora CP for an associate signal is applied to the signal. The CPs may becategorized according to length. For example, the CPs may be categorizedinto an Extended CP (Long CP), a Normal CP (Regular CP), a Short CP, andthe like.

A “signal” in the present embodiment can be rephrased as a radioresource, a resource, a channel, a physical channel, a logical channel,a carrier, a frequency, a carrier frequency, a band, a bandwidth, aradio wave, a signal waveform, a radio frame, a frame, a subframe, aslot, a resource block, a resource block set, a resource element, aresource element set, a symbol, a symbol set, an OFDM symbol, aDFT-S-OFDM symbol (SCFDMA symbol), a subcarrier, a subframe, a cell, aserving cell, a transport block, a Transmission Time Interval (TTI), orthe like.

In the present embodiment, it is apparent that a radio resource, aresource, a channel, a physical channel, a logical channel, a carrier, afrequency, a carrier frequency, a band, a bandwidth, a radio wave, asignal waveform, a radio frame, a frame, a subframe, a slot, a resourceblock, a resource block set, a resource element, a resource element set,a symbol, a symbol set, an OFDM symbol, a DFT-S-OFDM symbol (SCFDMAsymbol), a subcarrier, a subframe, a cell, a serving cell, a transportblock, a Transmission Time Interval (TTI), and the like can be rephrasedas a “signal”.

Some of or all the above signals may be transmitted at prescribedsubcarrier spacing. The “prescribed subcarrier spacing” may be referredto as a Predefined subcarrier spacing. The “subcarrier spacing” can berephrased as a “subcarrier bandwidth”, “subcarrier band”, “subcarrierfrequency” or a “subcarrier spacing”.

For example, the above-described prescribed subcarrier spacing may bedetermined based on some or all Element (1) to Element (4) below. Theprescribed subcarrier spacing may be determined based on any combinationof Element (1) to Element (4) below. Although “element” is used forexplanation in the present embodiment, “element” can be rephrased as“condition”, “requirement”, “cause”, “factor”, or the like.“Determination” in the present embodiment can be rephrased as“configuration”, “notification”, “transmission”, “application”, or thelike.

-   -   Element (1): Defined (specified) by a specification    -   Element (2): Explicitly configured and/or indicated    -   Element (3): Implicitly configured and/or indicated    -   Element (4): Capability information of a terminal apparatus        (configured and/or indicated based on capability information of        the terminal apparatus)

Element (2) may mean being configured and/or indicated based onexplicitly notified information.

Element (3) may mean being configured and/or indicated based onimplicitly notified information.

Elements are not limited to Element (1) to Element (4) and may use otherelements than Element (1) to Element (4) or may use some of Element (1)to Element (4).

An example of a subcarrier spacing determination method based on Element(1) will be described.

“Defined (specified) by a specification” in Element (1) can be rephrasedas “predefined”, “predefined by a specification”, “restricted by aspecification”, “allowed by a specification”, or the like. The“specification” can be rephrased as “written specification”, “standard”,or “written standard”.

The subcarrier spacing applicable to Element (1) may be defined by atable as in FIG. 17. The subcarrier spacing to be applied among definedsubcarrier spacings may be determined based on some or all Element (1)to Element (4). For example, the terminal apparatus may identify thesubcarrier spacing to be applied, by being notified by the base stationapparatus of an index (index number) in the table in FIG. 17.

The subcarrier spacing applicable to Element (1) may relate to anoperation mode. For example, the operation mode may be defined by atable as in FIG. 18. The operation mode to be applied may be determinedbased on some or all Element (1) to Element (4). For example, theterminal apparatus may identify the operation mode to be applied, bybeing notified by the base station apparatus of an index (index number)in the table in FIG. 18. The terminal apparatus identifying theoperation mode to be applied may mean the operation mode beingconfigured for the terminal apparatus.

The subcarrier spacing applicable to Element (1) may be more than one.In other words, the subcarrier spacing applicable to Element (1) may bedefined as an “applicable subcarrier spacing set”. For example, theapplicable subcarrier spacing set may be managed by a table as in FIG.19. For example, the terminal apparatus may identify the applicablesubcarrier spacing set, by being notified by the base station apparatusof an index (index number) in the table in FIG. 19. The applicablesubcarrier spacing may relate to an operation mode as described above.Furthermore, the applicable subcarrier spacing in the applicablesubcarrier spacing set (an actually applied subcarrier spacing in theapplicable subcarrier spacing set) may be determined based on some orall Element (1) to Element (4).

The applicable subcarrier spacing in Element (1) may relate to anoperating band. For example, the operating band may be defined by atable as in FIG. 20. The operating band to be applied is preferablydetermined based on some or all Element (1) to Element (4). For example,the terminal apparatus may identify the operating band to be applied, bybeing notified by the base station apparatus of an index (index number,number for managing the operating band, or an index indicating theoperating band number) in the table in FIG. 20. In other words, theterminal apparatus may identify the applicable subcarrier spacing, bybeing notified by the base station apparatus of an index in the table inFIG. 20. In other words, the terminal apparatus may (implicitly)identify the applicable subcarrier spacing, based on informationindicating the configured operating band. The terminal apparatusidentifying the operating band to be applied may mean the operating bandbeing configured for the terminal apparatus, the terminal apparatuscommunicating using the operating band, or the like.

The subcarrier spacing applicable to one operating band may be more thanone. In other words, the “applicable subcarrier spacing set” may bedefined for one operating band. For example, the subcarrier spacing setapplicable to one operating band may be managed by a table as in FIG.21. For example, the terminal apparatus may identify the operating bandto be applied by being notified by the base station apparatus of anindex (index number, number for managing the operating band, or an indexindicating the operating band number) in the table in FIG. 21. In otherwords, the terminal apparatus may identify the applicable subcarrierspacing set by being notified by the base station apparatus of an indexin the table in FIG. 21. In other words, the terminal apparatus may(implicitly) identify the applicable subcarrier spacing set, based oninformation indicating the configured operating band. Furthermore, theapplicable subcarrier spacing may be determined based on some or allElement (1) to Element (4) in the applicable subcarrier spacing set(actually applied subcarrier spacing in the applicable subcarrierspacing set).

The applicable subcarrier spacings may be defined independently for theuplink operating band and the downlink operating band. For example, theapplicable subcarrier spacings may be managed by a table as in FIG. 24.For example, a first uplink operating band and a first downlinkoperating band may correspond to a first operating band, and thesubcarrier spacing applicable to the first uplink operating band may bea first subcarrier spacing while a subcarrier spacing applicable to thefirst downlink operating band may be a second subcarrier spacing.

The applicable subcarrier spacing sets may be defined independently forthe uplink operating band and the downlink operating band. For example,the applicable subcarrier spacing sets may be managed by a table as inFIG. 25. For example, the first uplink operating band and the firstdownlink operating band may correspond to the first operating band, andthe subcarrier spacing set applicable to the first uplink operating bandmay be a first subcarrier spacing set while a subcarrier spacing setapplicable to the first downlink operating band may be a secondsubcarrier spacing set. The subcarrier spacings included in the firstsubcarrier spacing set and the second subcarrier spacing set may overlapwith each other.

For example, in a case that operating bands are managed by a table as inFIG. 20, FIG. 21, FIG. 24, or FIG. 25, the operating bands may bepreferably managed by a table, and a corresponding index is given toeach operating band managed by the table. The index is linked to acorresponding uplink operating band, a corresponding downlink operatingband, and a duplex mode. Note that the uplink operating band is anoperating band used for reception at the base station apparatus andtransmission at the terminal apparatus. The downlink operating band isan operating band used for transmission at the base station apparatusand reception at the terminal apparatus. Each of the uplink operatingband and the downlink operating band may be preferably given by a lowerlimit frequency and an upper limit frequency (associated frequencyband). The duplex mode may be preferably given by TDD or FDD. The duplexmode may be other than TDD and FDD. For example, the duplex mode may bea transmission burst (optionally including at least a downlink burst oran uplink burst). The duplex mode of the table may be a Frame structuretype. Frame structure type 1 is applicable to Frequency Division Duplex(FDD). Frame structure type 2 is applicable to Time Division Duplex(TDD). Frame structure type 3 is applicable to the operation of theLicensed Assisted Access (LAA) cell or the operation of the LicensedAssisted Access (LAA) secondary cell.

Although an example of notifying a subcarrier spacing to be appliedbased on information indicating the operating band or an applicablesubcarrier set has been described, the subcarrier spacing to be appliedor the applicable subcarrier spacing set may be notified based oninformation associated with indicating a parameter managed by a table asin FIG. 20, FIG. 21, FIG. 24, or FIG. 25. For example, informationindicating an uplink operating band may be notified, and the subcarrierspacing to be applied or the applicable subcarrier spacing set may benotified based on information indicating the uplink operating band. Forexample, information indicating a downlink operating band is notified,and the subcarrier spacing to be applied or the applicable subcarrierspacing set may be notified based on information indicating the downlinkoperating band. For example, information indicating the duplex mode or aFrame structure type may be notified, and the subcarrier spacing to beapplied or the applicable subcarrier spacing set may be notified basedon information indicating the duplex mode or the Frame structure type.

For example, in a case that the operating bands are managed by a tableas in FIG. 20, FIG. 21, FIG. 24, or FIG. 25, operating bands associatedwith an index “1” to an index “44” may be licensed bands (bands whichare not LAA), and operating bands associated with an index “45” may bean unlicensed band (LAA band).

Although not illustrated, other operating bands may be included in FIG.20, FIG. 21, FIG. 24, and FIG. 25. For example, operating bandsassociated with an index “252” to an index “255” may be unlicensed bands(LAA bands). Note that the uplink operating band is not preferablyapplied to the index “252” (n/a, not applicable). The 5150 MHz to 5250Hz is preferably applied to the downlink operating band. FDD ispreferably applied to the duplex mode. Furthermore, for the index “253”,the uplink operating band is preferably reserved (reserved to be used infuture), and the downlink operating band is preferably reserved. FDD ispreferably applied to the duplex mode. Furthermore, for the index “254”,the uplink operating band is preferably reserved (reserved to be used infuture), and the downlink operating band is preferably reserved. FDD ispreferably applied to the duplex mode. Note that the uplink operatingband is not preferably applied to the index “255” (n/a, not applicable).The 5725 MHz to 5850 Hz is preferably applied to the downlink operatingband. FDD is preferably applied to the duplex mode. Note that 5150 MHzto 5250 Hz and 5725 MHz to 5850 Hz are preferably unlicensed bands (LAAbands).

The “operating band” can be rephrased as a “band”, a “frequency”, a“carrier frequency”, or the like.

The applicable subcarrier spacing may be defined in the frequencydomain. In other words, the applicable subcarrier spacing may berestricted in the frequency domain. For example, the subcarrier spacingapplicable to the carrier frequency may be defined by a specification.In a case that multiple subcarrier spacings are applicable to a carrierfrequency, a subcarrier spacing set applicable to the carrier frequencymay be defined by a specification. The “applicable subcarrier spacingset” may include all or some of subcarrier spacings applicable to thecarrier frequency. The adaptable subcarrier spacing may be definedindependently for each carrier frequency. The adaptable subcarrierspacing set may be defined independently for each carrier frequency.

A “carrier frequency” can be rephrased as a radio resource, a resource,a channel, a physical channel, a logical channel, a carrier, afrequency, a band, a bandwidth, a radio wave, a signal waveform, a radioframe, a frame, a subframe, a slot, a resource block, a resource blockset, a resource element, a resource element set, a symbol, a symbol set,an OFDM symbol, a DFT-S-OFDM symbol (SCFDMA symbol), a subcarrier, asubframe, a cell, a serving cell, a transport block, a Transmission TimeInterval (TTI), or the like.

The applicable subcarrier spacing may be defined in the time domain. Inother words, the applicable subcarrier spacing may be restricted in thetime domain. For example, the applicable subcarrier spacing may bedefined by a specification, based on a unit (e.g., radio frame number,subframe number, slot number, or symbol number) defined in the timedomain. In a case that multiple subcarrier spacings are applicable tothe unit defined in the time domain, a subcarrier spacing set applicableto the unit defined in the time domain may be defined by aspecification. The “applicable subcarrier spacing set” may include allor some of subcarrier spacings applicable to the unit defined in thetime domain.

The applicable subcarrier spacing may be defined in the frequency domainand the time domain. In other words, the applicable subcarrier spacingmay be restricted in the frequency domain and the time domain.

The applicable subcarrier spacing may be defined for each type ofchannel and/or type of communication (type of information carried by asignal). In other words, the applicable subcarrier spacing may berestricted according to each type of channel and/or communication (typeof information carried by a signal).

For example, a subcarrier spacing applicable to a first channel (or asubcarrier spacing set applicable to the first channel) may be defined,a subcarrier spacing applicable to a second channel (or a subcarrierspacing set applicable to the second channel) may be defined, . . . ,and a subcarrier spacing applicable to an x-th channel (or a subcarrierspacing set applicable to the x-th channel) may be defined. At leastsome of or all the following channels may be included in the firstchannel to the x-th channel.

-   -   Channel associated with transmission of downlink control        information (e.g., Physical Downlink Control Channel, Enhanced        Physical Downlink Control Channel)    -   Channel associated with transmission of uplink control        information (e.g., Physical Uplink Control Channel)    -   Channel associated with transmission of downlink data (e.g.,        Physical Downlink Shared Channel)    -   Channel associated with transmission of uplink data (e.g.,        Physical Uplink Shared Channel)    -   Channel associated with random access (e.g., Physical Random        Access Channel)    -   Broadcast Channel (e.g., Physical Broadcast Channel)    -   Channel associated with transmission of information for        notification of the region in which information associated with        control is transmitted (e.g., Physical Control Format Indicator        Channel)    -   Channel associated with transmission of a HARQ indicator (HARQ        feedback or response information) indicating an ACKnowledgement        (ACK) or a Negative ACKnowledgement (NACK) for received data        (e.g., Physical Hybrid automatic repeat request Indicator        Channel)    -   Channel associated with multicast (e.g., Physical Multicast        Channel)

The downlink data may be referred to as downlink user data, and theuplink data may be referred to as uplink user data.

The downlink data and/or uplink data may be referred to simply as dataor user data.

In a case that multiple subcarrier spacings are applicable to a channel,a subcarrier spacing set applicable to the channel may be defined by aspecification. The “applicable subcarrier spacing set” may include allor some of subcarrier spacings applicable to the channel.

The “applicable subcarrier spacing” may be rephrased as a “candidate forsubcarrier spacing” or the like. The “applicable subcarrier spacing set”may be rephrased as a “set of candidates for subcarrier spacing” or thelike.

In a case that multiple applicable subcarrier spacings are determined(case that an applicable subcarrier spacing set is determined) based onElement (1), an applicable subcarrier spacing (subcarrier spacing to beactually applied in the applicable subcarrier spacing set) may furtherbe determined based on some or all Element (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(2) will be described.

Here, Element (2) may include some of or all Element (2-1) to Element(2-5) below. Alternatively, Element (2) may be determined based on anycombination of Element (2-1) to Element (2-5) below.

-   -   Element (2-1): configured and/or indicated based on higher layer        information    -   Element (2-2): configured and/or indicated based on broadcast        information    -   Element (2-3): configured and/or indicated based on information        transmitted in the physical layer    -   Element (2-4): configured and/or indicated based on information        transmitted individually for each terminal apparatus    -   Element (2-5): configured and/or indicated based on information        transmitted in common for multiple terminal apparatuses

Elements are not limited to Element (2-1) to Element (2-5), and may useother elements than Element (2-1) to Element (2-5) or may use some ofElement (2-1) to Element (2-5).

An example of a subcarrier spacing determination method based on Element(2-1) will be described.

The “higher layer information” in Element (2-1) can be rephrased ashigher layer information, information transmitted in a higher layer,information provided through higher layer signaling, higher layersignaling, a higher layer, or the like. The higher layer is preferably alayer higher than the physical layer and may be a Medium Access Control(MAC) layer or a Radio Resource Control (RRC) layer. The higher layerinformation may be dedicated signaling (Dedicatedsignaling). The“Dedicated signaling” may be terminal apparatus dedicated signaling orDedicated RRC signaling.

The “higher layer information” in Element (2-1) may be transmitted inthe Radio Resource Control (RRC) layer by using RRC signaling or may betransmitted in the Medium Access Control (MAC) layer by using a MAC CE.Here, the RRC signaling and/or the MAC CE is also referred to as higherlayer signaling. The RRC signaling and/or the MAC CE is included in atransport block.

The transport block and HARQ retransmission of the transport block aremapped to one serving cell. The transport block in the downlink may beMAC layer data transmitted on the DownLink Shared CHannel (DL-SCH).

In the uplink, “transport block”, “MAC Protocol Data Unit (PDU)”, “MAClayer data”, “DL-SCH”, “DL-SCH data”, and “uplink data” are assumed tomean the same.

For example, the higher layer information may be information relating toan applicable subcarrier spacing.

For example, the higher layer information may be information relating toan applicable subcarrier spacing set.

For example, the higher layer information may be information relating toa subcarrier spacing used for signal transmission. The higher layerinformation can be rephrased as “information relating to a subcarrierspacing to be used for signal transmission”, “information relating to asubcarrier spacing used for signal transmission”, “information relatingto a subcarrier spacing to be actually used for signal transmission”,“information relating to a subcarrier spacing actually used for signaltransmission”, or the like.

For example, the higher layer information may be information based onElement (1). For example, information transmitted in a higher layer maybe information defined by a specification.

The information relating to the applicable subcarrier spacing may betransmitted and/or configured independently for each carrier frequency.

In a case that multiple applicable subcarrier spacings are determined(case that an applicable subcarrier spacing set is determined) based onElement (2-1), an applicable subcarrier spacing (subcarrier spacing tobe actually applied in the applicable subcarrier spacing set) mayfurther be determined based on some or all Element (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(2-2) will be described.

The “broadcast information” in Element (2-2) can be rephrased asinformation transmitted on a Broadcast Channel (e.g., Physical BroadcastChannel), information to be broadcast, system information, or the like.“Broadcast” may mean the same information (information used in commonfor multiple terminal apparatuses) being transmitted for multipleterminal apparatuses.

A Master Information Block (MIB) (Broadcast Channel (BCH)) is preferablyused for “broadcast”, and the Master Information Block may betransmitted on a Broadcast Channel (e.g., Physical Broadcast Channel) ora channel associated with transmission of downlink user data (e.g.,Physical Downlink Shared Channel).

A System Information Block (MIB) (Broadcast Channel (BCH)) is preferablyused for “broadcast”, and the System Information Block may betransmitted on a Broadcast Channel (e.g., Physical Broadcast Channel) ora channel associated with transmission of downlink user data (e.g.,Physical Downlink Shared Channel).

The broadcast information may be transmitted on a channel associatedwith multicast (e.g., e.g., Physical Multicast Channel).

For example, the broadcast information may be information relating to anapplicable subcarrier spacing.

For example, the broadcast information may be information relating to anapplicable subcarrier spacing set.

For example, the broadcast information may be information relating to asubcarrier spacing used for signal transmission. The broadcastinformation can be rephrased as “information relating to a subcarrierspacing to be used for signal transmission”, “information relating tosubcarrier spacing used for signal transmission”, “information relatingto a subcarrier spacing to be actually used for signal transmission”,“information relating to a subcarrier spacing actually used for signaltransmission”, or the like.

For example, the broadcast information may be information based onElement (1). For example, the broadcast information may be informationdefined by a specification.

The information relating to the applicable subcarrier spacing may betransmitted and/or configured independently for each carrier frequency.

In a case that multiple applicable subcarrier spacings are determined(case that an applicable subcarrier spacing set is determined) based onElement (2-2), an applicable subcarrier spacing (subcarrier spacing tobe actually applied in the applicable subcarrier spacing set) mayfurther be determined based on some or all Element (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(2-3) will be described.

The “information transmitted in the physical layer” in Element (2-3) canbe rephrased as information transmitted via physical layer signalling,information transmitted on the physical channel, information transmittedin Layer 1 (L1), L1 signalling, or the like.

The “information transmitted in the physical layer” in Element (2-3) maybe transmitted on some or all the following channels.

-   -   Channel associated with transmission of downlink control        information (e.g., Physical Downlink Control Channel or Enhanced        Physical Downlink Control Channel)    -   Channel associate with transmission of uplink control        information (e.g., Physical Uplink Control Channel)    -   Channel associated with transmission of downlink user data        (e.g., Physical Downlink Shared Channel)    -   Channel associated with transmission of uplink user data (e.g.,        Physical Uplink Shared Channel)    -   Channel associated with random access (e.g., Physical Random        Access Channel)    -   Broadcast Channel (e.g., Physical Broadcast Channel)    -   Channel associated with transmission of information for        notification of the region in which information associated with        control is transmitted (e.g., Physical Control Format Indicator        Channel)    -   Channel associated with transmission of a HARQ indicator (HARQ        feedback or response information) indicating an ACKnowledgement        (ACK) or a Negative ACKnowledgement (NACK) for received data        (e.g., Physical Hybrid automatic repeat request Indicator        Channel)    -   Channel associated with multicast (e.g., Physical Multicast        Channel)

The “channel” can be rephrased as a “signal”, a “signal associated witha channel”, a “signal for transmitting a channel”, or the like.

For example, first information may be transmitted on some of or all theabove channels. The first information may be information relating to anapplicable subcarrier spacing and/or information relating to anapplicable subcarrier spacing set. The first information may beinformation relating to a subcarrier spacing to be actually applied inthe applicable subcarrier spacing set.

For example, the first information may be transmitted on some of or allthe above channels, and further second information transmission may betransmitted on some of or all the above channels. The first informationmay be information relating to an applicable subcarrier spacing set, andthe second information may be information relating to a subcarrierspacing to be actually applied in the applicable subcarrier spacing setindicated by the first information. The first information may betransmitted by using higher layer signaling, and the second informationmay be transmitted by using physical layer signalling.

For example, first information may be transmitted on some of or all theabove channels. The first information may be downlink allocationinformation (downlink channel assignment information or PDSCH assignmentinformation) or uplink assignment information (uplink channel assignmentinformation or PUSCH assignment information), and a subcarrier spacingmay be specified based on whether the first information is downlinkassignment information or uplink assignment information. In other words,in a case that the first information is downlink assignment information,a first subcarrier spacing is applied to a channel assigned by the firstinformation (downlink channel); in a case that the first information isuplink assignment information, a second subcarrier spacing is applied toa channel assigned by the first information (uplink channel). In otherwords, depending on whether the channel assignment information is fordownlink channel assignment or not (for uplink allocation), a subcarrierspacing to be applied to a channel assigned by the information ispreferably determined (specified).

The first information may be information based on Element (1). Forexample, the first information may be information defined by aspecification.

For example, the above “first information” may be transmitted asdownlink control information. “Transmitted as downlink controlinformation” may mean being set in a field (e.g., Subcarrier-spaceindication field or Subcarrier-spacing indication field) defined in aformat for downlink control information (e.g., Downlink ControlInformation Format) for transmission. The format for downlink controlinformation may be transmitted on a channel associated with transmissionof downlink control information (e.g., Physical Downlink Control Channelor Enhanced Physical Downlink Control Channel.

In a case that the first information is included in the downlink controlinformation, the downlink control information may further include afield (Downlink assignment field) for assigning a channel associatedwith transmission of downlink user data (e.g., Physical Downlink SharedChannel) and/or a field (Uplink assignment field) for assigning achannel associated with transmission of uplink user data (e.g., PhysicalUplink Shared Channel). The subcarrier spacing indicated by the firstinformation may be applied to transmission of downlink user data and/oruplink data assigned by the field for assigning a channel associatedwith transmission of downlink user data and/or the field for assigning achannel associated with transmission of uplink user data.

In other words, a subcarrier spacing for the second channel may bedetermined based on the first information transmitted on the firstchannel. The first channel and the second channel may be the same.

In a case that multiple applicable subcarrier spacings are determined(case that an applicable subcarrier spacing set is determined) based onElement (2-3), an applicable subcarrier spacing (subcarrier spacing tobe actually applied in the applicable subcarrier spacing set) mayfurther be determined based on some or all Element (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(2-4) will be described.

The “information transmitted individually for each terminal apparatus”in Element (2-4) may be information relating to an applicable subcarrierspacing.

The “information transmitted individually for each terminal apparatus”in Element (2-4) may be information relating to an applicable subcarrierspacing set.

The “information transmitted individually for each terminal apparatus”in Element (2-4) may be information relating to a subcarrier spacing tobe used for signal transmission. The “information relating to asubcarrier spacing to be used for signal transmission” can be rephrasedas “information relating to subcarrier spacing used for signaltransmission”, “information relating to a subcarrier spacing to beactually used for signal transmission”, “information relating to asubcarrier spacing actually used for signal transmission”, or the like.

The “information transmitted individually for each terminal apparatus”in Element (2-4) may be information based on Element (1). For example,information transmitted in a higher layer may be information defined bya specification.

In a case that multiple applicable subcarrier spacings are determined(case that an applicable subcarrier spacing set is determined) based onElement (2-4), an applicable subcarrier spacing (subcarrier spacing tobe actually applied in the applicable subcarrier spacing set) mayfurther be determined based on some or all Element (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(2-5) will be described.

The “information transmitted in common for multiple terminalapparatuses” in Element (2-5) may be information relating to anapplicable subcarrier spacing.

The “information transmitted in common for multiple terminalapparatuses” in Element (2-5) may be information relating to anapplicable subcarrier spacing set.

The “information transmitted in common for multiple terminalapparatuses” in Element (2-5) may be information relating to asubcarrier spacing to be used for signal transmission. The “informationrelating to a subcarrier spacing to be used for signal transmission” canbe rephrased as “information relating to subcarrier spacing used forsignal transmission”, “information relating to a subcarrier spacing tobe actually used for signal transmission”, “information relating to asubcarrier spacing actually used for signal transmission”, or the like.

The “information transmitted in common for multiple terminalapparatuses” in Element (2-5) may be information based on Element (1).For example, information transmitted in a higher layer may beinformation defined by a specification.

In a case that multiple applicable subcarricr spacings are determined(case that an applicable subcarricr spacing set is determined) based onElement (2-5), an applicable subcarrier spacing (subcarrier spacing tobe actually applied in the applicable subcarrier spacing set) mayfurther be determined based on some or all Element (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(3) will be described.

Here, Element (3) may include some of or all Element (3-1) to Element(3-6) below. Alternatively, Element (3) may be determined based on anycombination of Element (3-1) to Element (3-6) below.

-   -   Element (3-1): configured and/or indicated based on information        obtained by blind detection    -   Element (3-2): configured and/or indicated based on service        (based on information associated with service)    -   Element (3-3): configured and/or indicated based on Logical        Channel ID (LCID)    -   Element (3-4): configured and/or indicated based on a bearer    -   Element (3-5): configured and/or indicated based on a band        (carrier frequency)    -   Element (3-6): configured and/or indicated based on a signal        (channel) transmission pattern

Elements are not limited to Element (3-1) to Element (3-6) and may useother elements than Element (3-1) to Element (3-6) or may use some ofElement (3-1) to Element (3-6).

An example of a subcarrier spacing determination method based on Element(3-1) will be described.

The “blind detection” in Element (3-1) means that information on thesubcarrier spacing at which the first signal is to be transmitted isunknown to a receiver (terminal apparatus) and is detected by thereceiver without any prior information (in a blind manner). The“detection” can be rephrased as “decoding”, “demodulation”, “sensing”,or the like.

The “blind detection” in Element (3-1) means that detection of a signal(or channel) is attempted for each (monitored/possible) subcarriercandidate.

For example, the subcarrier spacing for the first signal is unknown tothe terminal apparatus, and the terminal apparatus detects a subcarrierspacing for the first signal without any prior information (in a blindmanner). For example, in a case that the terminal apparatus attempts toreceive the first signal at multiple subcarrier spacings andsuccessfully receives the first signal by using a certain one of thesubcarrier spacings, the terminal apparatus detects (interprets) thissubcarrier spacing as a subcarrier spacing used for transmission of thefirst signal.

Alternatively, a subcarrier spacing candidate having a possibility ofbeing used for transmission of the first signal (or a subcarrier spacingcandidate set having a possibility of being used for transmission of thefirst signal) may be determined and/or configured. For example, in acase that the terminal apparatus (receiver) attempts to receive thefirst signal by using the determined and/or configured subcarrierspacing candidates and successfully receives the first signal by using acertain subcarrier spacing, the terminal apparatus detects (interprets)this subcarrier spacing as a subcarrier spacing used for transmission ofthe first signal. The “subcarrier spacing candidate having a possibilityof being used for transmission of the first signal (or a subcarrierspacing candidate set having a possibility of being used fortransmission of the signal)” may be determined based on some of or allElement (1) to Element (4). The “subcarrier spacing candidate having apossibility of being used for transmission of the first signal (or asubcarrier spacing candidate set having a possibility of being used fortransmission of the signal)” may be rephrased as a “subcarrier spacingcandidate for the first signal” or the like.

A success in receiving the first signal may be determined based onCyclic Redundancy Check (CRC) (CRC code or CRC parity bits).

In a case that the terminal apparatus that has successfully detected asubcarrier spacing for the first signal receives the first signal(attempts to receive the first signal) at another frequency and/or time,the terminal apparatus may attempt the reception by assuming that thefirst signal is being transmitted by using the detected subcarrierspacing.

The “first signal” can be rephrased as a “signal”, an “x-th signal(where x is any number)”, a “certain signal”, a “specific signal”, orthe like.

In a case that multiple applicable subcarrier spacings are determined(case that an applicable subcarrier spacing set is determined) based onElement (3-1), an applicable subcarrier spacing (subcarrier spacing tobe actually applied in the applicable subcarrier spacing set) mayfurther be determined based on some or all Element (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(3-2) will be described.

The “service” in Element (3-2) may be service in which the terminalapparatus is interested or may be service for which the terminalapparatus is approved. The “service” can be rephrased as a “specificservice”, a “certain service”, a “first service”, an “x-th service(where x is any number)”, or the like. The “service” may be differentfor Device to Device communication (D2D), communication between a basestation and a terminal apparatus (cellular communication), Machine toMachine communication (M2M), Internet of Things (IoT), unicasttransmission, multicast transmission (communication associated withMBSFN), MBSFN group, traveling speed of terminal apparatus, and thelike.

For example, in a case that the terminal apparatus receives a signalassociated with the first service, the signal associated with the firstservice is preferably received (reception of the signal is preferablyattempted) by assuming that the signal is transmitted at the firstsubcarrier spacing. The “case that the terminal apparatus receives asignal associated with the first service” can be rephrased as a “casethat the terminal apparatus receives a signal for the first service”, a“case that the terminal apparatus receives a signal associated withspecific service”, a “case that the terminal apparatus receives a signalfor specific service”, or the like. The first subcarrier spacing assumedby the terminal apparatus may be determined based on some or all Element(1) to Element (4).

Alternatively, a subcarrier spacing candidate having a possibility ofbeing used for the first service (or a subcarrier spacing candidate sethaving a possibility of being used for the first service) may bedetermined and/or configured. The “subcarrier spacing candidate having apossibility of being used for the first service (or a subcarrier spacingcandidate set having a possibility of being used for the first service)”may be determined based on some of or all Element (1) to Element (4).The subcarrier spacing actually used for the first service among thesubcarrier spacing candidates having a possibility of being used for thefirst service may be determined based on some of or all Element (1) toElement (4). “Used for the first service” may be rephrased as “used forsignal transmission for the first service” or the like.

In a case that multiple applicable subcarrier spacings are determined(case that an applicable subcarrier spacing set is determined) based onElement (3-2), an applicable subcarrier spacing (subcarrier spacing tobe actually applied in the applicable subcarrier spacing set) mayfurther be determined based on some or all Element (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(3-3) will be described.

The “Logical Channel ID (LCID)” in Element (3-3) may be one ofconstituent elements of a MAC header and may be an identifier (ID)associated with indicating (instructing) an attribute or destination ofcorresponding MAC data. For example, the LCID indicates whether or notthe corresponding MAC data is a signal for control. For example, theLCID indicates whether or not the corresponding MAC data is a signal fordata (user data). For example, the LCID indicates whether thecorresponding MAC data is a signal for control or a signal for data(user data). For example, the LCID indicates whether or not thecorresponding MAC data is a signal for paging.

For example, in a case that the terminal apparatus receives a MAC headerincluding an LCID, the subcarrier spacing for the signal associated withthe LCID may be determined based on the LCID. The “signal associatedwith the LCID” may be a signal in which the MAC data corresponding tothe LCID is transmitted.

For example, in a case that the terminal apparatus receives a MAC headerincluding an LCID, the subcarrier spacing for the signal associated withthe LCID may be determined based on the attribute and/or destination ofthe MAC data indicated by the LCID. The “signal associated with theLCID” may be a signal in which the MAC data corresponding to the LCID istransmitted. “Based on the attribute and/or destination of the MAC dataindicated by the LCID” may mean being based on the LCID indicatingwhether the corresponding MAC data is a signal for control or a signalfor data (user data).

The subcarrier spacing for the signal associated with the LCID may bedetermined based on some or all Element (1) to Element (4).

Alternatively, a subcarrier spacing candidate having a possibility ofbeing used for the signal associated with the LCID (or a subcarrierspacing candidate set having a possibility of being used for the signalassociated with the LCID) may be determined and/or configured. The“subcarrier spacing candidate having a possibility of being used for thesignal associated with the LCID (or a subcarrier spacing candidate sethaving a possibility of being used for the signal associated with theLCID)” may be determined based on some of or all Element (1) to Element(4). The subcarrier spacing to be actually used as the signal associatedwith the LCID among the subcarrier spacing candidates having apossibility of being used for the signal associated with the LCID may bedetermined based on some of or all Element (1) to Element (4).

Element (3-3) may mean being configured and/or indicated based onpriority of the channel (logical channel) associated with the LCID. Forexample, the priority of the channel (logical channel) associated withthe LCID is preferably determined based on whether the MAC datacorresponding to the LCID is a signal for control or a signal for data(user data), and the signal for control may be given higher prioritythan that of the signal for data (user data).

In a case that multiple applicable subcarrier spacings are determined(case that an applicable subcarrier spacing set is determined) based onElement (3-3), an applicable subcarrier spacing (subcarrier spacing tobe actually applied in the applicable subcarrier spacing set) mayfurther be determined based on some or all Element (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(3-4) will be described.

An example of a subcarrier spacing determination method based on Element(3-4) will be described.

Downlink data and uplink data may include Signalling Radio Bearer (SRB)data and Data Radio Bearer (DRB) data. The SRB is defined as a radiobearer used only for transmission of a Radio Resource Control (RRC)message and a Non Access Stratum (NAS) message. The DRB is defined as aradio bearer for transmitting user data.

The SRB may include SRB0, SRB1, and SRB2. SRB0 is an SRB for an RRCmessage using a CCCH logical channel. SRB1 is an SRB for an RRC messageusing a DCCH logical channel (the RRC message may include a piggy-backNAS message). SRB1 is an SRB for a NAS message using a DCCH logicalchannel (the NAS message is a NAS message prior to establishment ofSRB2). SRB2 is an SRB for an RRC message using a DCCH logical channel(the RRC message includes logged measurement information). The loggedmeasurement information may be measurement information regularly loggedwith time. SRB2 has a lower priority than that of SRB1. SRB2 isconfigured by an E-UTRAN after security is activated.

“Based on a bearer” in Element (3-4) may mean being based on downlinkdata and/or uplink data including (or being based on downlink dataand/or uplink data not including) Signalling Radio Bearer (SRB) data.For example, in a case that downlink data and/or uplink data includesSignalling Radio Bearer (SRB) data, the first subcarrier spacing may beapplied to transmission or reception of the downlink data and/or theuplink data. In other cases (a case that downlink data and/or uplinkdata does not include Signalling Radio Bearer (SRB) data or a case thatdownlink data and/or uplink data includes Data Radio Bearer (DRB) data),the second subcarrier spacing may be applied to transmission orreception of the downlink data and/or the uplink data.

“Based on a bearer” in Element (3-4) may mean being based on downlinkdata and/or uplink data including (or being based on downlink dataand/or uplink data not including) Data Radio Bearer (DRB) data. Forexample, in a case that downlink data and/or uplink data includes DataRadio Bearer (DRB) data, the first subcarrier spacing may be applied totransmission or reception of the downlink data and/or the uplink data.In other cases (case that downlink data and/or uplink data does notinclude Data Radio Bearer (DRB) data or case that downlink data and/oruplink data includes Signalling Radio Bearer (SRB) data), the secondsubcarrier spacing may be applied to transmission or reception of thedownlink data and/or the uplink data.

“Based on a bearer” in Element (3-4) may mean being based on any ofSRB0, SRB1, and SRB2 included in the SRB. For example, in a case thatSRB0 is included in the SRB, the first subcarrier spacing may beapplied; in a case that SRB1 is included in the SRB, the secondsubcarrier spacing may be applied; in a case that SRB2 is included inthe SRB, the third subcarrier spacing may be applied.

In a case that multiple applicable subcarrier spacings are determined(case that an applicable subcarrier spacing set is determined) based onElement (3-4), an applicable subcarrier spacing (subcarrier spacing tobe actually applied in the applicable subcarrier spacing set) mayfurther be determined based on some or all Element (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(3-5) will be described.

The “band (carrier frequency)” in Element (3-5) may mean band (carrierfrequency) used for transmission and/or reception of some or allsignals. Transmission and/or reception of some or all signals may beperformed by a terminal apparatus or a base station apparatus.

The “band (carrier frequency)” in Element (3-5) may mean band (carrierfrequency) having a possibility of being used for transmission and/orreception of some or all signals. An assumption of having a possibilitythat some or all signals are transmitted and/or received may be made bya terminal apparatus or a base station apparatus.

The “band (carrier frequency)” in Element (3-5) may mean band (carrierfrequency) for which transmission and/or reception of some or allsignals is assumed. An assumption (expectation) of transmission and/orreception of some or all signals may be made by a terminal apparatus ora base station apparatus. In other words, the “band (carrier frequency)”in Element (3-5) may mean a band (carrier frequency) for whichtransmission and/or reception of some or all signals is assumed. Anassumption of transmission and/or reception of some or all signals maybe made by a terminal apparatus or a base station apparatus.

“Assumption” in the present embodiment may be rephrased as“expectation”, “attempt”, “attempt detection”, or the like.

“Transmit” in the present embodiment may be rephrased as “attempttransmission” or the like. “Receive” in the present embodiment may berephrased as “attempt reception”, “attempt detection”, or the like.

The “band” in the present embodiment may be rephrased as an “operatingband”, and an uplink operating band and a downlink operating band maycorrespond to the operating band. At least a downlink operating band maycorrespond to the operating band. In other words, the operating band maynot necessarily include an uplink operating band.

For example, in a case that the terminal apparatus receives some or allsignals above at a first carrier frequency, the terminal apparatus mayreceive the signals by assuming that the first subcarrier spacing isapplied at the first carrier frequency (a signal using the firstsubcarrier spacing is transmitted).

In other words, the first carrier frequency and the first subcarrierspacing may correspond to each other. In other words, the firstsubcarrier spacing may be applied to some or all signals abovetransmitted and/or received at the first carrier frequency.

For example, in a case that the terminal apparatus receives some or allsignals at the first carrier frequency, the terminal apparatus mayreceive the signals by assuming that any of subcarrier spacings includedin the first subcarrier spacing candidate set is applied at the firstcarrier frequency. “Any of subcarrier spacings included in the firstsubcarrier spacing candidate set is applied” may be determined based onsome or all Element (1) to Element (4).

In other words, the first carrier frequency and the first subcarrierspacing candidate set may correspond to each other. Specifically, anyone subcarrier spacing included in the first subcarrier spacingcandidate set may be applied to some or all signals above transmittedand/or received at the first carrier frequency. For example, multiplesubcarrier spacings may be included in the first subcarrier spacingcandidate set. For example, the first subcarrier spacing to the x-thsubcarrier spacing (where x is any number) may be included in the firstsubcarrier spacing candidate set. The subcarrier spacing actuallyapplied among the first subcarrier spacing to the x-th subcarrierspacing (where x is any number) may be determined based on some or allElement (1) to Element (4).

An example of a subcarrier spacing determination method based on Element(3-6) will be described.

The “signal (channel) transmission pattern” in Element (3-6) may bedifferent depending on frequency (frequency position) and/or time (timeposition) at which a signal is transmitted. For Example, a first signaltransmitted at a first frequency and/or a first time may be a firstsignal transmitted in a first transmission pattern; a first signaltransmitted at a second frequency and/or a second time may be a firstsignal transmitted in a second transmission pattern. Although“transmission” of a base station apparatus has been described here, thismay be rephrased as “reception” of a terminal apparatus. In other words,“transmission” in the present embodiment may be rephrased as“reception”, and a “signal (channel) transmission pattern” may berephrased as a “signal reception pattern”.

For example, in a case that the terminal apparatus has received thefirst signal transmitted in the first transmission pattern, the terminalapparatus may receive the second signal by assuming that the firstsubcarrier spacing is applied to transmission of the second signal; in acase that the terminal apparatus has received the first signaltransmitted in the second transmission pattern, the terminal apparatusmay receive the second signal by assuming that the second subcarrierspacing is applied to transmission of the second signal. A prescribedsubcarrier spacing (predefined subcarrier spacing or subcarrier spacingdefined in a written specification or the like) may be applied to thetransmission of the first signal.

For example, in a case that the terminal apparatus has received aSynchronization signal transmitted in the first transmission pattern,the terminal apparatus may receive a signal for data by assuming thatthe first subcarrier spacing is applied to transmission of the signalfor data; in a case that the terminal apparatus has received aSynchronization signal transmitted in the second transmission pattern,the terminal apparatus may receive a signal for data by assuming thatthe second subcarrier spacing is applied to transmission of the signalfor data. A prescribed subcarrier spacing (predefined subcarrier spacingor subcarrier spacing defined in a written specification or the like)may be applied to the transmission of the Synchronization signal.

For example, in a case that the terminal apparatus has received aSynchronization signal transmitted in the first transmission pattern,the terminal apparatus may receive a signal for system information(Broadcast Channel) by assuming that the first subcarrier spacing isapplied to transmission of the signal for system information; in a casethat the terminal apparatus has received a Synchronization signaltransmitted in the second transmission pattern, the terminal apparatusmay receive a signal for system information by assuming that the secondsubcarrier spacing is applied to transmission of the signal for systeminformation. A prescribed subcarrier spacing (predefined subcarrierspacing or subcarrier spacing defined in a written specification or thelike) may be applied to the transmission of the Synchronization signal.

An example of a subcarrier spacing determination method based on Element(4) will be described.

The “capability information of a terminal apparatus” in Element (4) maybe capability information of a terminal apparatus associated with theterminal apparatus supporting (or not supporting) specificcommunication. The “specific communication” may be communication(communication system) to which multiple subcarrier spacings areadaptable.

The “capability information of a terminal apparatus” in Element (4) maybe capability information of a terminal apparatus associated with asubcarrier spacing.

The “capability information of a terminal apparatus” may be capabilityinformation of a terminal apparatus associated with supporting (or notsupporting) transmission and/or reception using multiple subcarrierspacings. “Transmission and/or reception using multiple subcarrierspacings” may mean that multiple subcarrier spacings are applicable tosignal transmission and/or reception. “Transmission and/or receptionusing multiple subcarrier spacings” may mean that variable subcarrierspacings are applicable to signal transmission and/or reception.

The “capability information of a terminal apparatus” may be capabilityinformation of a terminal associated with supporting (or not supporting)transmission and/or reception using a prescribed subcarrier spacing.

The above “capability information of a terminal apparatus” may indicatethe number of channels (cells or component carriers) that the terminalapparatus can receive simultaneously and the subcarrier spacingcorresponding to each of the channels (cells or component carriers). Forexample, the above “capability information of a terminal apparatus” mayindicate that two channels (cells or component carriers) using the firstsubcarrier spacing and one channel (cell or component carrier) using thesecond subcarrier spacing can be received simultaneously.

The above “capability information of a terminal apparatus” may indicatethe number of channels (cells or component carriers) that the terminalapparatus can transmit simultaneously and the subcarrier spacingcorresponding to each of the channels. For example, the above“capability information of a terminal apparatus” may indicate that twochannels (cells or component carriers) using the first subcarrierspacing and one channel (cell or component carrier) using the secondsubcarrier spacing can be transmitted simultaneously.

The above “capability information of a terminal apparatus” may bedefined for each carrier frequency (each band). For example, theterminal apparatus may hold and transmit the “capability information ofa terminal apparatus” for each carrier frequency (each band).

The above “capability information of a terminal apparatus” may bedefined independently for uplink and downlink. Specifically, the above“capability information of a terminal apparatus” may be definedindependently for capability information for the terminal apparatusassociated with uplink communication and capability information of theterminal apparatus for downlink communication. For example, the terminalapparatus may hold and transmit the “capability information of aterminal apparatus” independently for uplink and downlink and performtransmission accordingly.

The terminal apparatus may transmit the “capability information of theterminal apparatus”, based on the capability information associated witha subcarrier spacing usable for a base station or network and thesubcarrier spacing supported by the terminal apparatus. The “capabilityinformation associated with a subcarrier spacing usable for a basestation or network” may be broadcast by a base station apparatus ortransmitted as system information.

For example, in a case that the terminal apparatus having a capabilityassociated with transmitting and/or receiving a signal using the firstto third subcarrier spacings finds out that the first subcarrier spacingand the third subcarrier spacing are the subcarrier spacings usable fora base station or network, based on the “capability informationassociated with a subcarrier spacing usable for a base station ornetwork”, the terminal apparatus may transmit information of having thecapability associated with transmitting and/or receiving a signal usingthe first subcarrier spacing and the third subcarrier spacing, as the“capability information of a terminal apparatus”.

The “capability information of a terminal apparatus” may be transmittedin a case of receiving a terminal capability enquiry(UECapabilityEnquiry) message from a base station.

An example of a procedure for transmitting the “capability informationof a terminal apparatus” will be described.

The base station apparatus transmits a terminal capability enquiry(UECapabilityEnquiry) message to a terminal apparatus. The terminalcapability enquiry message is used for requesting transmission of theradio access capability of the terminal apparatus. The terminalapparatus transmits a terminal capability information(UECapabilityInformation) message to the base station apparatus, basedon the terminal capability enquiry message. The terminal capabilityinformation message is used for transmitting the radio access capabilityof the terminal apparatus that has been requested by the base stationapparatus. The terminal capability information message includes aterminal capability (UE-EUTRA-Capability) information element. TheUE-EUTRA-Capability is used to convey, to the network, the radio accesscapability parameter of the terminal apparatus at the base stationapparatus and a Feature group indicator (FGI) for mandatory features.

The UE-EUTRA-Capability includes at least parameters related to theradio frequency (RF-Parameters) and parameters related to the physicallayer (PhyLayerParameters). The RF-Parameters includes at least a listof the bands supported by the terminal apparatus(supportedBandListEUTRA) and/or a combination of the bands supported bythe terminal apparatus (supportedBandCombination). ThesupportedBandListEUTRA is a list of the bands (SupportedBandEUTRA)supported by the terminal apparatus. The supportedBandCombination is alist of the parameters (BandCombinationParameters) related to thecombination of the bands supported by the terminal apparatus.

The SupportedBandEUTRA includes at least an indicator(FreqBandIndicator) indicating the band supported by the terminalapparatus and information (halfDulplex) indicating whether half-duplexcommunication or full-duplex communication is supported in the band. Thenumber of bands in which communication is supported by the terminalapparatus is not limited. In other words, the terminal apparatus maysupport communication in one band only, or the terminal apparatus maysupport communication in multiple bands.

The BandCombinationParamaters includes parameters (BandParameters)related to each band in the combination of the bands supported by theterminal apparatus. The BandParameters includes an indicator(FreqBandIndicator) indicating the band, parameters (BandParametersUL)related to the uplink in the band, and parameters (BandParametersDL)related to the downlink in the band. The BandParametersUL is a list ofthe parameters (CA-MIMO-ParametersUL) related to CA and MIMO in theuplink. The BandParametersDL is a list of the parameters(CA-MIMO-ParametersDL) related to CA and MIMO in the downlink. TheCA-MIMO-ParametersUL includes information (CA-BandwidthClass) indicatingthe CA bandwidth class in the uplink, and information(MIMO-CapabilityUL) related to the number of MIMO layers supported inthe uplink. The CA-MIMO-ParametersDL includes information(CA-BandwidthClass) indicating the CA bandwidth class in the downlink,and information (MIMO-CapabilityDL) related to the number of MIMO layerssupported in the downlink. The terminal apparatus explicitly includesall the supported CA bandwidth classes in the signalling related to theband combination in the CA-BandwidthClass.

In a case that multiple applicable subcarrier spacings are determined(case that an applicable subcarrier spacing set is determined) based onElement (4), an applicable subcarrier spacing (a subcarrier spacing tobe actually applied in the applicable subcarrier spacing set) mayfurther be determined based on some or all Element (1) to Element (4).

In a case that a subcarrier spacing for a signal is determined based onsome of or all Element (1) to Element (4) above, a reference signal forthe signal and/or a CP (CP length) for the signal may be determinedbased on the determined subcarrier spacing. In other words, a referencesignal for the signal and/or a CP (CP length) for the signal may bedetermined based on the subcarrier spacing for the signal beingdetermined. The “reference signal for the signal is determined” may meanthe subcarrier spacing for the reference signal being determined. Thedetermined CP (CP length) may be applied also to the determinedreference signal.

For example, the reference signal corresponding to the subcarrierspacing (subcarrier spacing of the reference signal) and/or CP (CPlength) may be defined by a specification. In other words, the referencesignal corresponding to the subcarrier spacing (subcarrier spacing ofthe reference signal) and/or CP (CP length) for part of or entire signalmay be defined by a specification.

The reference signal for the signal (subcarrier spacing of the referencesignal) and/or CP (CP length) may be notified by a base station.

The reference signal for the signal (subcarrier spacing of the referencesignal) and/or the CP (CP length) may be defined by a specification. Forexample, the reference signal for the signal (subcarrier spacing of thereference signal) and/or CP (CP length) may correspond to a carrierfrequency (band). In other words, the terminal apparatus may identifythe reference signal for the signal (subcarrier spacing of the referencesignal) and/or the CP (CP length) by identifying the carrier frequency(band) for the signal.

A terminal apparatus according to an aspect of the present inventionincludes: a control unit configured to identify a subcarrier spacing setapplicable to a data channel, based on a first parameter included inhigher layer signaling; and a reception unit configured to receive acontrol channel including data channel assignment information. Based onthe type of the data channel assignment information, the terminalapparatus selects, from the subcarrier spacing set, a subcarrier spacingapplicable to the data channel assigned based on the data channelassignment information.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, and the first parameter relatesto an operating band.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, and an uplink operating band anda downlink operating band correspond to the operating band, and asubcarrier spacing applicable to the uplink operating band and asubcarrier spacing applicable to the downlink operating band are definedindependently.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, and the type of the data channelassignment information includes a first type associated with uplink datachannel assignment information and a second type associated withdownlink data channel assignment information.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, wherein the terminal apparatusapplies a first subcarrier spacing in the applicable subcarrier spacingset to the uplink data channel in a case that the type of the datachannel assignment information is the first type, while applying asecond subcarrier spacing in the applicable subcarrier spacing set tothe downlink data channel in a case that the type of the data channelassignment information is the second type.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, and the subcarrier spacing setincludes a first subset and a second subset. The terminal apparatusapplies a first subcarrier spacing included in the first subset to theuplink data channel in a case that the type of the data channelassignment information is the first type, while applying a secondsubcarrier spacing included in the second subset to the downlink datachannel in a case that the type of the data channel assignmentinformation is the second type.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, and the first subcarrier spacingand/or the second subcarrier spacing is indicated by using broadcastinformation, information common to multiple terminal apparatuses,information dedicated to a single terminal apparatus, physical layerinformation, and/or higher layer information.

A base station apparatus according to an aspect of the present inventionincludes: a transmission unit configured to transmit higher layersignaling including a first parameter associated with indicating asubcarrier spacing set applicable to a data channel; a transmission unitconfigured to transmit a control channel including data channelassignment information; and a transmission unit configured to transmit adata channel by using an applicable subcarrier spacing based on the typeof the data channel assignment information. The applicable subcarrierspacing is included in the subcarrier spacing set.

A base station apparatus according to an aspect of the present inventionis the above-described base station apparatus, and the first parameterrelates to an operating band.

A base station apparatus according to an aspect of the present inventionis the above-described base station apparatus, and an uplink operatingband and a downlink operating band correspond to the operating band, anda subcarrier spacing applicable to the uplink operating band and asubcarrier spacing applicable to the downlink operating band are definedindependently.

A base station apparatus according to an aspect of the present inventionis the above-described base station apparatus, and the type of the datachannel assignment information includes a first type associated withuplink data channel assignment information and a second type associatedwith downlink data channel assignment information.

A base station apparatus according to an aspect of the present inventionis the above-described base station apparatus, wherein the base stationapparatus applies a first subcarrier spacing in the applicablesubcarrier spacing set to the uplink data channel in a case that thetype of the data channel assignment information is the first type, whileapplying a second subcarrier spacing in the applicable subcarrierspacing set to the downlink data channel in a case that the type of thedata channel assignment information is the second type.

A base station apparatus according to an aspect of the present inventionis the above-described base station apparatus, and the subcarrierspacing set includes a first subset and a second subset. The basestation apparatus applies a first subcarrier spacing in the first subsetto the uplink data channel in a case that the type of the data channelassignment information is the first type, while applying a secondsubcarrier spacing in the second subset to the downlink data channel ina case that the type of the data channel assignment information is thesecond type.

A base station apparatus according to an aspect of the present inventionis the above-described base station apparatus, and the first subcarrierspacing and/or the second subcarrier spacing is indicated by usingbroadcast information, information common to multiple terminalapparatuses, information dedicated to one terminal apparatus, physicallayer information, and/or higher layer information.

A communication method for a terminal apparatus according to an aspectof the present invention includes the steps of: identifying a subcarrierspacing set applicable to a data channel, based on a first parameterincluded in higher layer signaling; receiving a control channelincluding data channel assignment information; and selecting, based onthe type of the data channel assignment information, a subcarrierspacing applicable to the data channel associated with the data channelassignment information, from the subcarrier spacing set.

A communication method for a base station apparatus according to anaspect of the present invention includes the steps of: transmittinghigher layer signaling including a first parameter associated withindicating a subcarrier spacing set applicable to a data channel;transmitting a control channel including data channel assignmentinformation; and transmitting a data channel by using an applicablesubcarrier spacing based on the type of the data channel assignmentinformation. The applicable subcarrier spacing is included in thesubcarrier spacing set.

A terminal apparatus according to an aspect of the invention includes: areception unit configured to receive a control channel with aninformation control information format including a first field and asecond field; a reception control unit configured to identify asubcarrier spacing, based on a value of the first field; and a receptionunit configured to receive a data channel assigned based on a value ofthe second field by using the identified subcarrier spacing.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, wherein the terminal apparatusis notified of whether or not the first field is present, through higherlayer signaling, and receives, in a case of being notified that thefirst field is present, the control information format of a payload sizewith the first field, while receiving, in a case of not being notifiedthat the first field is present, the control information format of apayload size without the first field.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, wherein the terminal apparatusis notified of whether or not the control channel and the data channelhave different subcarrier spacings, through higher layer signaling, andreceives, in a case of being notified that the control channel and thedata channel have different subcarrier spacings, the control informationformat of a payload size with the first field, while receiving, in acase of not being notified that the control channel and the data channelhave different subcarrier spacings, the control information format of apayload size without the first field.

A base station apparatus according to an aspect of the present inventionincludes: a transmission unit configured to transmit a control channelwith an information control information format including a first fieldand a second field; and a transmission unit configured to transmit adata channel assigned based on a value of the second field by using asubcarrier spacing based on a value of the first field.

A base station apparatus according to an aspect of the present inventionis the above-described base station apparatus, wherein the base stationapparatus makes notification of whether or not the first field ispresent, through higher layer signaling, and transmits, in a case ofmaking notification that the first field is present, the controlinformation format of a payload size with the first field, whiletransmitting, in a case of not making notification that the first fieldis present, the control information format of a payload size without thefirst field.

A base station apparatus according to an aspect of the present inventionis the above-described base station apparatus, wherein the base stationapparatus makes notification of whether or not the control channel andthe data channel have different subcarrier spacings, through higherlayer signaling, and transmits, in a case of making notification thatthe control channel and the data channel have different subcarrier, thecontrol information format of a payload size with the first field, whiletransmitting, in a case of not making notification that the controlchannel and the data channel have different subcarrier spacing, thecontrol information format of a payload size without the first field.

A communication method for a terminal apparatus according to an aspectof the invention includes the steps of: receiving a control channel withan information control information format including a first field and asecond field; identifying a subcarrier spacing, based on a value of thefirst field; and receiving a data channel assigned based on a value ofthe second field by using the identified subcarrier spacing.

A communication method for a base station apparatus according to anaspect of the present invention includes the steps of: transmitting acontrol channel with an information control information format includinga first field and a second field; and transmitting a data channelassigned based on a value of the second field by using a subcarrierspacing based on a value of the first field.

A terminal apparatus according to an aspect of the invention includes: areception unit configured to receive a Synchronization signal by using aprescribed first subcarrier spacing; a reception control unit configuredto identify a second subcarrier spacing to be used for transmission of afirst signal, based on the received Synchronization signal; and areception unit configured to receive the first signal by using theidentified second subcarrier spacing.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, and the first signal is a signaldifferent from the signal, and the first signal is used for datatransmission.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, and the terminal apparatusidentifies the second subcarrier spacing to be used for transmission ofthe first signal, based on a pattern in which the Synchronization signalis transmitted.

A terminal apparatus according to an aspect of the invention includes: areception unit configured to receive a Synchronization signal by using aprescribed first subcarrier spacing; a reception unit configured toreceive system information after synchronization based on theSynchronization signal; a reception control unit configured to identifya second subcarrier spacing to be used for transmission of a firstsignal, based on first information included in the system information;and a reception unit configured to receive the first signal by using theidentified second subcarrier spacing.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, and the system information isreceived by using the first subcarrier spacing.

A terminal apparatus according to an aspect of the present invention isthe above-described terminal apparatus, and the first information isinformation indicating an operating mode.

A communication method for a terminal apparatus according to an aspectof the invention includes the steps of: receiving a Synchronizationsignal by using a prescribed first subcarrier spacing; identifying asecond subcarrier spacing to be used for transmission of a first signal,based on the received Synchronization signal; and receiving the firstsignal by using the identified second subcarrier spacing.

A communication method for a terminal apparatus according to an aspectof the present invention is the above-described communication method fora terminal apparatus, and the first signal is a signal different fromthe signal, and the first signal is used for data transmission.

A communication method for a terminal apparatus according to an aspectof the present invention is the above-described communication method fora terminal apparatus, and the second subcarrier spacing to be used fortransmission of the first signal is identified based on a pattern inwhich the Synchronization signal is transmitted.

A communication method for a terminal apparatus according to an aspectof the invention includes the steps of: receiving a Synchronizationsignal by using a prescribed first subcarrier spacing; receiving systeminformation after synchronization based on the Synchronization signal;identifying a second subcarrier spacing to be used for transmission of afirst signal, based on first information included in the systeminformation; and receiving the first signal by using the identifiedsecond subcarrier spacing.

A communication method for a terminal apparatus according to an aspectof the present invention is the above-described communication method fora terminal apparatus, and the system information is received by usingthe first subcarrier spacing.

A communication method for a terminal apparatus according to an aspectof the present invention is the above-described communication method fora terminal apparatus, and the first information is informationindicating an operating mode.

A program running on each of the base station apparatus and the terminalapparatus according to the present invention may serve as a program thatcontrols a Central Processing Unit (CPU) and the like (a program forcausing a computer to operate) in such a manner as to enable thefunctions according to the above-described embodiment of the presentinvention. The information handled in these apparatuses is temporarilystored in a Random Access Memory (RAM) while being processed.Thereafter, the information is stored in various types of Read OnlyMemory (ROM) such as a Flash ROM and a Hard Disk Drive (HDD), and whennecessary, is read by the CPU to be modified or rewritten.

Note that the terminal apparatus and the base station apparatus −1 orthe base station apparatus −2 according to the above-describedembodiments may be partially realized by the computer. In this case,this configuration may be realized by recording a program for realizingsuch control functions on a computer-readable recording medium andcausing a computer system to read the program recorded on the recordingmedium for execution.

The “computer system” here is defined as a computer system built intothe terminal apparatus or the base station apparatus −1 or the basestation apparatus −2, and the computer system includes an OS andhardware components such as peripheral devices. Furthermore, the“computer-readable recording medium” refers to a portable medium such asa flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and astorage device such as a hard disk built into the computer system.

Moreover, the “computer-readable recording medium” may include a mediumthat dynamically retains the program for a short period of time, such asa communication line that is used to transmit the program over a networksuch as the Internet or over a communication line such as a telephoneline, and a medium that retains, in that case, the program for a fixedperiod of time, such as a volatile memory within the computer systemwhich functions as a server or a client. Furthermore, the program may beconfigured to realize some of the functions described above, and alsomay be configured to be capable of realizing the functions describedabove in combination with a program already recorded in the computersystem.

The base station apparatus −1 or base station apparatus −2 according tothe above-described embodiments can be realized as an aggregation(apparatus group) constituted of multiple apparatuses. Each of theapparatuses constituting the apparatus group may be equipped with someor all portions of each function or each functional block of the basestation apparatus −1 or base station apparatus −2 according to theabove-described embodiments. It is only required that the apparatusgroup itself include general functions or general functional blocks ofthe base station apparatus −1 or base station apparatus −2. Furthermore,the terminal apparatus in the above-described embodiments can alsocommunicate with the base station apparatus as an aggregate.

Furthermore, the base station apparatus −1 or base station apparatus −2according to the above-described embodiments may be an Evolved UniversalTerrestrial Radio Access Network (EUTRAN). Furthermore, the base stationapparatus −1 or base station apparatus −2 according to theabove-described embodiments may have some or all portions of a functionof a higher node for an eNodeB.

Furthermore, some or all portions of each of the terminal apparatus andthe base station apparatus −1 or base station apparatus −2 according tothe above-described embodiments may be typically achieved as aLarge-Scale Integration (LSI) that is an integrated circuit or may berealized as a chip set. The functional blocks of each of the terminalapparatus and the base station apparatus −1 or base station apparatus −2may be individually realized as a chip, or some or all of the functionalblocks may be integrated into a chip. Furthermore, a circuit integrationtechnique is not limited to the LSI, and may be realized with adedicated circuit or a general-purpose processor. Furthermore, in a casethat with advances in semiconductor technology, a circuit integrationtechnology with which an LSI is replaced appears, it is also possible touse an integrated circuit based on the technology.

Furthermore, according to the above-described embodiments, a cellularmobile station apparatus is described as one example of a terminalapparatus or a communication device, but the invention of thisapplication is not limited to this, and can be applied to a fixed-typeelectronic apparatus installed indoors or outdoors, or a stationary-typeelectronic apparatus, for example, a terminal apparatus or acommunication device, such as an Audio-Video (AV) apparatus, a kitchenapparatus, a cleaning or washing machine, an air-conditioning apparatus,office equipment, a vending machine, and other household apparatuses.

The embodiments of the present invention have been described in detailabove referring to the drawings, but the specific configuration is notlimited to the embodiments and includes, for example, an amendment to adesign that falls within the scope that does not depart from the gist ofthe present invention. Furthermore, various modifications are possiblewithin the scope of the present invention defined by claims, andembodiments that are made by suitably combining technical meansdisclosed according to the different embodiments are also included inthe technical scope of the present invention. Furthermore, aconfiguration in which a constituent element that achieves the sameeffect is substituted for the one that is described in the embodimentsis also included in the technical scope of the present invention.

CROSS-REFERENCE OF RELATED APPLICATION

This application claims the benefit of priority to JP 2016-019538 filedin Japan on Feb. 4, 2016, which is incorporated herein by reference inits entirety.

REFERENCE SIGNS LIST

-   2201 Higher layer-   2202 Control unit-   2203 Codeword generation unit-   2204 Downlink subframe generation unit-   2205 Downlink reference signal generation unit-   2206 OFDM signal transmission unit-   2207 Base station transmit antenna-   2208 Base station receive antenna-   2209 SC-FDMA signal reception unit-   2210 Uplink subframe processing unit-   2211 Uplink control information extraction unit-   2301 Terminal receive antenna-   2302 OFDM signal reception unit-   2303 Downlink subframe processing unit-   2304 Downlink reference signal extraction unit-   2305 Transport block extraction unit-   2306 Control unit-   2307 Higher layer-   2308 Channel state measurement unit-   2309 Uplink subframe generation unit-   2310 Uplink control information generation unit-   2311, 2312 SC-FDMA signal transmission unit-   2313, 2314 Terminal transmit antenna

The invention claimed is:
 1. A user equipment, comprising: a receptioncircuit configured to receive higher layer signaling including firstinformation relating to a measurement object; and a measurement circuitconfigured to perform, based on the measurement object, a Radio ResourceManagement (RRM) measurement; wherein in a case where the measurementobject indicates a Channel State Information reference signal (CSI-RS)measurement, the first information includes a first parameter indicatinga subcarrier spacing of the CSI-RS that is used for the RRM measurement,the subcarrier spacing of the CSI-RS is configured independently of asubcarrier spacing of a downlink physical channel in a serving cell inwhich the CSI-RS is transmitted, and each of (a) the subcarrier spacingof the CSI-RS and (b) the subcarrier spacing of the downlink physicalchannel is configured independently of a subcarrier spacing of an uplinkphysical channel in the serving cell.
 2. A method at a user equipment,the method comprising the steps of: receiving higher layer signalingincluding first information relating to a measurement object; andperforming, based on the measurement object, a Radio Resource Management(RRM) measurement; wherein in a case where the measurement objectindicates a Channel State Information reference signal (CSI-RS)measurement, the first information includes a first parameter indicatinga subcarrier spacing of the CSI-RS that is used for the RRM measurement,the subcarrier spacing of the CSI-RS is configured independently of asubcarrier spacing of a downlink physical channel in a serving cell inwhich the CSI-RS is transmitted, and each of (a) the subcarrier spacingof the CSI-RS and (b) the subcarrier spacing of the downlink physicalchannel is configured independently of a subcarrier spacing of an uplinkphysical channel in the serving cell.
 3. A base station, comprising: ageneration circuit configured to generate higher layer signalingincluding first information relating to a measurement object; and atransmission circuit configured to transmit the higher layer signaling;wherein the measurement object relates to a Radio Resource Management(RRM) measurement, in a case where the measurement object indicates aChannel State Information reference signal (CSI-RS) measurement, thefirst information includes a first parameter indicating a subcarrierspacing of the CSI-RS that is used for the RRM measurement, thesubcarrier of the CSI-RS is configured independently of a subcarrierspacing of a downlink physical channel in a serving cell in which theCSI-RS is transmitted, and each of (a) the subcarrier spacing of theCSI-RS and (b) the subcarrier spacing of the downlink physical channelis configured independently of a subcarrier spacing of an uplinkphysical channel in the serving cell.
 4. A method at a base station, themethod comprising the steps of: generating higher layer signalingincluding first information relating to a measurement object; andtransmitting the higher layer signaling; wherein the measurement objectrelates to a Radio Resource Management (RRM) measurement, in a casewhere the measurement object indicates a Channel State Informationreference signal (CSI-RS) measurement, the first information includes afirst parameter indicating a subcarrier spacing of the CSI-RS that isused for the RRM measurement, the subcarrier spacing of the CSI-RS isconfigured independently of a subcarrier spacing of a downlink physicalchannel in a serving cell in which the CSI-RS is transmitted, and eachof (a) the subcarrier spacing of the CSI-RS and (b) the subcarrierspacing of the downlink physical channel is configured independently ofa subcarrier spacing of an uplink physical channel in the serving cell.